most unethical animal experiments

6 Horrific Experiments on Animals and What You Can Do to End Cruel Tests

Posted by Priya S on August 13, 2019 | Permalink

It’s  estimated that  a round   115 million  animals are used in cruel and archaic experiments   worldwide every year  – a number that ‘ s almost impossible to imagine.  Experimenters drill holes into alligators ‘  skulls, clone and castrate monkeys ,  and  purposely damage  the inside s  of dogs ‘  mouths  –  all   in the name of science.  

  Because the results of these  inhumane  tests are  nearly always  irrelevant to humans, many of the diseases that experimenters  say they ‘ re attempting to  study  are left without  effective   treatments and  cures. Therefore, human patients end up suffering ,  too.  

 The following are just a few examples of the procedures that experimenters have conducted on animals: 

1. Experimenters Drugged Alligators and Drilled Holes  I nto  Their  Skulls   

In the US, 40  alligators were  imprisoned and  drugged with  k etamine before experimenters fixed head-restraining devices to their snouts with cement, drilled holes into their skulls ,  and attached electrodes to their brains.  This is  no way to treat  any sentient being .  

Chinese  experimenters  genetically manipulated monkeys  so that they’d  be plagued with  mental health issues,  including  anxiety, fear, depression, behaviour associated with schizophrenia, and sleep  disorders – and then cloned them .

The  experimenters  plan to  create  a whole  colony  of  monkeys  who are likely to experience  the most  severe forms of psychological suffering .  Genetically manipulating and cloning animals won ‘ t solve human medical problems but certainly  will  cause these intelligent ,  sensitive beings a lifetime of misery.  

In a Swedish  laboratory ,  experimenters  took six black Labradors – Mimosa,  Milia , Luna, Venus, Lotus, and  Zuri  –  removed the ir  teeth ,  and cut apart the ir  gums ,   likely  subjecting them to  swelling and bleeding. The  dogs  were also put at risk of suffering from chronic pain  as a result of  nerve damage or infection. After the tests,  they were killed  and further experimented on  – treated as if they were nothing more than test tubes with tails.   

  Dogs ‘  status as  “ man ‘ s best friend “ offers them no protection from being  locked up in laboratories   and forced to endure excruciating procedures.  

 4. Experimenters Castrated Monkeys and Regrew Their Testicles  

Experimenters  castrated five young monkeys, chopped  their testicles into tiny pieces, and  then regrew these organs on their backs  in an attempt to produce viable sperm . It ‘ s as disturbing as it is sadistic – and these monkeys weren ‘ t the only victims.  Grady,  the only  “ healthy “  individual born from 138 fertilised eggs and dubbed the  “ success story “  in this horror show, is the product of cruel  Frankenscience . She ‘ ll likely spend the rest of her life under the clinical lights of the laboratory, confined to a cramped cage and subjected to painful, intrusive procedures. 

M onkeys aren ‘ t miniature humans: fundamental differences exist between  our  species – from the DNA, cells, and tissues to the reproductive biology – often resulting in one catastrophic failed experiment after another.  

Octopuses aren ‘ t under-evolved humans, but  some   experimenters  seem to think  they are . A mother octopus  and her eggs were  captured from the ocean so that experimenters in the US could use her offspring to test psychiatric drugs.  The  octopuses  were isolated  in small tanks for seven months before  being  transport ed to another facility, where they were  kept in buckets containing artificial seawater.  They were  then  forced to   absorb  the drug MDMA (ecstasy)   through their gills. 

The experimenters  claimed that their outlandish study lays the foundations for further testing of psychiatric drugs on these intelligent, mysterious marine animals – even though the results of test s on animals  are  often  unreliable and inapplicable to humans.  

6. Pregnant Mothers Force- Fed Viagra -Like Pills

Viagra-like pills  (sildenafil)  have been  repeatedly force-fed  to  or injected into dogs, mice, rabbits, and sheep . Even   pregnant  animals   have been given the drug  with the express intention of causing them to suffer from pre-eclampsia  – t heir  offspring  were then killed and dissected, either before or shortly after birth.  

  In another study ,  sildenafil  decreased the mortality rate of rat foetuses whose mothers had been injected with the drug. But results from experiments on animals don ‘ t translate well to humans.   Experimenters  gave  sildenafil  to pregnant  human  women whose placentas were   underperforming, telling them that the drug could help by improving blood supply through the placenta and promoting the growth of the foetus in the womb. Tragically,  11  babies died as a result of lung problems associated with the drug . These fatal side effects weren ‘ t predicted  by any of  the tests conducted on animals .  

  What You Can Do   

Experiments using animals are unethical and wasteful and produce misleading results because of fundamental biological and metaboli c differences between species.  Experimenters  must  switch to  innovative, non-animal, human-relevant methods – such as computer models that can accurately simulate what happens in humans, organs-on-chips, and 3-dimensional human tissue cultures – in order to advance medicine and spare animals   unconscionable cruelty.  

  Please click the button below to take five crucial actions  –  firing off e-mails to decision-makers and  adding your name to petitions and open letters  – to help animals trapped in laboratories . It only takes 30 seconds, and every signature makes a difference for animals.  

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• Future Perfect

What’s worse than a cruel animal experiment? A cruel and fake animal experiment.

Raising the consequences for animal testing experiments gone wrong.

by Marina Bolotnikova

Last December, in the wake of animal cruelty allegations against Elon Musk’s brain chip startup Neuralink, Vox’s Kenny Torrella wrote about a concept he called “the moral math of animal testing”: the view held by many people that trading some amount of animal suffering is worth it if it can save enough human lives by advancing medicine.

Experimentation on live animals is a divisive, morally charged subject. Slightly more than half of Americans say they oppose using animals in scientific research, according to a 2018 Pew survey, but it depends a lot on how you phrase the question and who is asking. When asked by the biomedical industry whether they support “the humane use of animals” to develop “lifesaving medicines,” many more people say they do, or aren’t sure. These gaps reflect the public’s lack of understanding of how vivisection works in general: Most people don’t know whether animal testing is humane, effective, or necessary, nor do they always know how to define those terms.

Not everyone will agree with my view of vivisection, which is that it’s unjustifiable in nearly all circumstances. But I would think most people will agree that animal experiments should have to clear an especially high bar — that they have to be truly necessary for saving human lives and irreplaceable with non-animal methods.

That is, unfortunately, not how animal testing in the US works at all. Scientists harm and kill animals for all sorts of studies that have nothing to do with saving human lives. Researchers at Oregon Health & Science University, for example, have forced prairie voles to drink alcohol to test whether it makes them cheat on their partners. A Harvard neuroscientist recently came under fire for separating caged mother monkeys from their babies and giving them surrogate stuffed animals to bond with, thus demonstrating, she wrote in a top scientific journal, that “infant/mother bonds may be triggered by soft touch.”

The worst kind of fraud

Animal experimentation is also not immune to outright fraud, a problem that’s “disturbingly common” in science, as Vox’s Kelsey Piper wrote in June. Last week, federal investigators found that William Armstead, a former professor at the University of Pennsylvania’s medical school, had faked the results of multiple federally funded studies that involved cutting open piglets’ skulls and inducing brain injuries. The studies were meant to test drugs for treating brain injuries in humans. (Armstead left the university while he was under investigation for this misconduct.)

Some of Armstead’s fabrications, which included relabeling results from past studies as new ones, appear designed to make a drug his team was studying look more effective, Ivan Oransky, co-founder of Retraction Watch — a blog that tracks retractions of scientific papers — told the Philadelphia Inquirer last week. Armstead’s team doctored 51 scientific figures across five published studies, three federal grant applications, and other documents. The faked data renders the research useless; it’s now been retracted from journals and can’t be incorporated into future work. “A bunch of pigs were subjected to some pretty terrible conditions for no reason,” Oransky told the Inquirer.

Armstead now faces a seven-year ban on conducting federally funded research, a penalty that’s relatively rare in its severity. But his case isn’t an isolated one.

Last year, a pivotal 2006 mouse study, which had been thought to shed light on the pathology of Alzheimer’s disease and shaped years of federally funded research, was credibly accused of being fraudulent and remains under investigation.

Also last year, federal officials found Deepak Kaushal, then-head of the federally funded Southwest National Primate Research Center in San Antonio, to have falsified results in a published study of a tuberculosis treatment tested on monkeys, and used those results in two NIH grant applications. Kaushal was placed under a one-year supervision period — the lightest imaginable slap on the wrist — with no lasting consequences for his ability to experiment on animals. He also, according to initial reports, got to keep his job as director of the lab. After criticism from some in the research community and animal advocates, he was later demoted from that position; it’s unclear whether he’ll be reinstated after his supervision period.

The price of suffering

All these revelations should raise alarms about how misconduct is handled in research involving animal testing. When a top primate researcher is allowed to keep experimenting on monkeys after falsifying data, it sends a message to everyone in the research community that recklessly handling animal experiments, while temporarily embarrassing, may not be that big a deal.

“The NIH tends to give anybody on their pay line the benefit of the doubt,” neuroscientist Katherine Roe, who worked at NIH for more than eight years and is now chief of PETA’s science advancement and outreach division, told me. (PETA, despite its reputation, has a top-notch team of scientists challenging unethical animal research). “The penalties for research fraud are not what they should be.”

To shift the incentive structure, we need better federal regulation that raises the cost of torturing animals for botched experiments. Right now, the consequences for misconduct in federally funded research don’t take into account whether the work involved animal testing, Roe said. Federal research regulations could be amended so that scientists found responsible for misconduct in work involving vulnerable populations, including non-human animals, be permanently barred from testing on them in future federally sponsored research, a change that’s been proposed by PETA, explained Emily Trunnell, a senior scientist for the organization.

That would be a good start. But it would require the authorities who oversee science to view the animal experiments themselves, and not just lying about their results, as morally implicated, something the research community has been loath to do because it threatens to undermine the whole endeavor of animal testing.

On a higher level, we have to start seeing it as the public’s right and duty to make democratic decisions about whether and how animals are used in scientific research, especially when our money is paying for it. Scientists are an exalted class, often allowed to self-regulate, but their expertise in a narrow subject matter shouldn’t let them overrule democratic governance of research ethics. Ethics belongs to us all. And the public expects a much higher bar than too many animal researchers currently set for themselves.

• Animal Welfare

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• 20 Most Unethical Experiments in Psychology

Humanity often pays a high price for progress and understanding — at least, that seems to be the case in many famous psychological experiments. Human experimentation is a very interesting topic in the world of human psychology. While some famous experiments in psychology have left test subjects temporarily distressed, others have left their participants with life-long psychological issues . In either case, it’s easy to ask the question: “What’s ethical when it comes to science?” Then there are the experiments that involve children, animals, and test subjects who are unaware they’re being experimented on. How far is too far, if the result means a better understanding of the human mind and behavior ? We think we’ve found 20 answers to that question with our list of the most unethical experiments in psychology .

Emma Eckstein

Electroshock Therapy on Children

Operation Midnight Climax

The Monster Study

Project MKUltra

The Aversion Project

Unnecessary Sexual Reassignment

Stanford Prison Experiment

Milgram Experiment

The Monkey Drug Trials

Featured Programs

Facial expressions experiment.

Little Albert

Bobo Doll Experiment

The Pit of Despair

The Bystander Effect

Learned Helplessness Experiment

Racism Among Elementary School Students

UCLA Schizophrenia Experiments

The Good Samaritan Experiment

Robbers Cave Experiment

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Controversial and Unethical Psychology Experiments

There have been a number of famous psychology experiments that are considered controversial, inhumane, unethical, and even downright cruel—here are five examples. Thanks to ethical codes and institutional review boards, most of these experiments could never be performed today.

At a Glance

Some of the most controversial and unethical experiments in psychology include Harlow's monkey experiments, Milgram's obedience experiments, Zimbardo's prison experiment, Watson's Little Albert experiment, and Seligman's learned helplessness experiment.

These and other controversial experiments led to the formation of rules and guidelines for performing ethical and humane research studies.

Harlow's Pit of Despair

Psychologist Harry Harlow performed a series of experiments in the 1960s designed to explore the powerful effects that love and attachment have on normal development. In these experiments, Harlow isolated young rhesus monkeys, depriving them of their mothers and keeping them from interacting with other monkeys.

The experiments were often shockingly cruel, and the results were just as devastating.

The Experiment

The infant monkeys in some experiments were separated from their real mothers and then raised by "wire" mothers. One of the surrogate mothers was made purely of wire.

While it provided food, it offered no softness or comfort. The other surrogate mother was made of wire and cloth, offering some degree of comfort to the infant monkeys.

Harlow found that while the monkeys would go to the wire mother for nourishment, they preferred the soft, cloth mother for comfort.

Some of Harlow's experiments involved isolating the young monkey in what he termed a "pit of despair." This was essentially an isolation chamber. Young monkeys were placed in the isolation chambers for as long as 10 weeks.

Other monkeys were isolated for as long as a year. Within just a few days, the infant monkeys would begin huddling in the corner of the chamber, remaining motionless.

The Results

Harlow's distressing research resulted in monkeys with severe emotional and social disturbances. They lacked social skills and were unable to play with other monkeys.

They were also incapable of normal sexual behavior, so Harlow devised yet another horrifying device, which he referred to as a "rape rack." The isolated monkeys were tied down in a mating position to be bred.

Not surprisingly, the isolated monkeys also ended up being incapable of taking care of their offspring, neglecting and abusing their young.

Harlow's experiments were finally halted in 1985 when the American Psychological Association passed rules regarding treating people and animals in research.

Milgram's Shocking Obedience Experiments

Isabelle Adam/Flickr/CC BY-NC-ND 2.0

If someone told you to deliver a painful, possibly fatal shock to another human being, would you do it? The vast majority of us would say that we absolutely would never do such a thing, but one controversial psychology experiment challenged this basic assumption.

Social psychologist Stanley Milgram conducted a series of experiments to explore the nature of obedience . Milgram's premise was that people would often go to great, sometimes dangerous, or even immoral, lengths to obey an authority figure.

The Experiments

In Milgram's experiment, subjects were ordered to deliver increasingly strong electrical shocks to another person. While the person in question was simply an actor who was pretending, the subjects themselves fully believed that the other person was actually being shocked.

The voltage levels started out at 30 volts and increased in 15-volt increments up to a maximum of 450 volts. The switches were also labeled with phrases including "slight shock," "medium shock," and "danger: severe shock." The maximum shock level was simply labeled with an ominous "XXX."​

The results of the experiment were nothing short of astonishing. Many participants were willing to deliver the maximum level of shock, even when the person pretending to be shocked was begging to be released or complaining of a heart condition.

Milgram's experiment revealed stunning information about the lengths that people are willing to go in order to obey, but it also caused considerable distress for the participants involved.

Zimbardo's Simulated Prison Experiment

 Darrin Klimek / Getty Images

Psychologist Philip Zimbardo went to high school with Stanley Milgram and had an interest in how situational variables contribute to social behavior.

In his famous and controversial experiment, he set up a mock prison in the basement of the psychology department at Stanford University. Participants were then randomly assigned to be either prisoners or guards. Zimbardo himself served as the prison warden.

The researchers attempted to make a realistic situation, even "arresting" the prisoners and bringing them into the mock prison. Prisoners were placed in uniforms, while the guards were told that they needed to maintain control of the prison without resorting to force or violence.

When the prisoners began to ignore orders, the guards began to utilize tactics that included humiliation and solitary confinement to punish and control the prisoners.

While the experiment was originally scheduled to last two full weeks it had to be halted after just six days. Why? Because the prison guards had started abusing their authority and were treating the prisoners cruelly. The prisoners, on the other hand, started to display signs of anxiety and emotional distress.

It wasn't until a graduate student (and Zimbardo's future wife) Christina Maslach visited the mock prison that it became clear that the situation was out of control and had gone too far. Maslach was appalled at what was going on and voiced her distress. Zimbardo then decided to call off the experiment.

Zimbardo later suggested that "although we ended the study a week earlier than planned, we did not end it soon enough."

Watson and Rayner's Little Albert Experiment

If you have ever taken an Introduction to Psychology class, then you are probably at least a little familiar with Little Albert.

Behaviorist John Watson  and his assistant Rosalie Rayner conditioned a boy to fear a white rat, and this fear even generalized to other white objects including stuffed toys and Watson's own beard.

Obviously, this type of experiment is considered very controversial today. Frightening an infant and purposely conditioning the child to be afraid is clearly unethical.

As the story goes, the boy and his mother moved away before Watson and Rayner could decondition the child, so many people have wondered if there might be a man out there with a mysterious phobia of furry white objects.

Controversy

Some researchers have suggested that the boy at the center of the study was actually a cognitively impaired boy who ended up dying of hydrocephalus when he was just six years old. If this is true, it makes Watson's study even more disturbing and controversial.

However, more recent evidence suggests that the real Little Albert was actually a boy named William Albert Barger.

Seligman's Look Into Learned Helplessness

During the late 1960s, psychologists Martin Seligman and Steven F. Maier conducted experiments that involved conditioning dogs to expect an electrical shock after hearing a tone. Seligman and Maier observed some unexpected results.

When initially placed in a shuttle box in which one side was electrified, the dogs would quickly jump over a low barrier to escape the shocks. Next, the dogs were strapped into a harness where the shocks were unavoidable.

After being conditioned to expect a shock that they could not escape, the dogs were once again placed in the shuttlebox. Instead of jumping over the low barrier to escape, the dogs made no efforts to escape the box.

Instead, they simply lay down, whined and whimpered. Since they had previously learned that no escape was possible, they made no effort to change their circumstances. The researchers called this behavior learned helplessness .

Seligman's work is considered controversial because of the mistreating the animals involved in the study.

Impact of Unethical Experiments in Psychology

Many of the psychology experiments performed in the past simply would not be possible today, thanks to ethical guidelines that direct how studies are performed and how participants are treated. While these controversial experiments are often disturbing, we can still learn some important things about human and animal behavior from their results.

Perhaps most importantly, some of these controversial experiments led directly to the formation of rules and guidelines for performing psychology studies.

Blum, Deborah.  Love at Goon Park: Harry Harlow and the science of affection . New York: Basic Books; 2011.

Sperry L.  Mental Health and Mental Disorders: an Encyclopedia of Conditions, Treatments, and Well-Being . Santa Barbara, CA: Greenwood, an imprint of ABC-CLIO, LLC; 2016.

Marcus S. Obedience to Authority An Experimental View. By Stanley Milgram. illustrated . New York: Harper &. The New York Times. 

Le Texier T. Debunking the Stanford Prison Experiment .  Am Psychol . 2019;74(7):823‐839. doi:10.1037/amp0000401

Fridlund AJ, Beck HP, Goldie WD, Irons G.  Little Albert: A neurologically impaired child .  Hist Psychol.  2012;15(4):302-27. doi:10.1037/a0026720

Powell RA, Digdon N, Harris B, Smithson C. Correcting the record on Watson, Rayner, and Little Albert: Albert Barger as "psychology's lost boy" .  Am Psychol . 2014;69(6):600‐611. doi:10.1037/a0036854

Seligman ME. Learned helplessness .  Annu Rev Med . 1972;23:407‐412. doi:10.1146/annurev.me.23.020172.002203

By Kendra Cherry, MSEd Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."

Should Animals Be Used for Scientific or Commercial Testing?

• History of Animal Testing

Animals are used to develop medical treatments, determine the toxicity of medications, check the safety of products destined for human use, and other  biomedical , commercial, and health care uses. Research on living animals has been practiced since at least 500 BC.

Descriptions of the dissection of live animals have been found in ancient Greek writings from as early as circa 500 BC. Physician-scientists such as  Aristotle ,  Herophilus , and  Erasistratus  performed the experiments to discover the functions of living organisms.  Vivisection  (dissection of a living organism) was practiced on human criminals in ancient Rome and Alexandria, but prohibitions against mutilation of the human body in ancient Greece led to a reliance on animal subjects. Aristotle believed that animals lacked intelligence, and so the notions of justice and injustice did not apply to them.  Theophrastus , a successor to Aristotle, disagreed, objecting to the vivisection of animals on the grounds that, like humans, they can feel pain, and causing pain to animals was an affront to the gods. Read more background…

Pro & Con Arguments

Pro 1 Animal testing contributes to life-saving cures and treatments for humans and animals alike. Nearly every medical breakthrough in the last 100 years has resulted directly from research using animals, according to the California Biomedical Research Association. To name just a few examples, animal research has contributed to major advances in treating conditions including breast cancer, brain injury, childhood leukemia, cystic fibrosis, multiple sclerosis, and tuberculosis. Testing on animals was also instrumental in the development of pacemakers, cardiac valve substitutes, and anesthetics. [ 9 ] [ 10 ] [ 11 ] [ 12 ] [ 13 ] Scientists racing to develop a vaccine for coronavirus during the 2020 global pandemic needed to test on genetically modified mice to ensure that the vaccine did not make the virus worse. Nikolai Petrovsky, professor in the College of Medicine and Public Health at Flinders University in Australia, said testing a coronavirus vaccine on animals is “absolutely essential” and skipping that step would be “fraught with difficulty and danger.” [ 119 ] [ 133 ] Researchers have to test extensively to prevent “vaccine enhancement,” a situation in which a vaccine actually makes the disease worse in some people. “The way you reduce that risk is first you show it does not occur in laboratory animals,” explains Peter Hotez, Dean for the National School of Tropical Medicine at Baylor College. [ 119 ] [ 141 ] Further, animals themselves benefit from the results of animal testing. Vaccines tested on animals have saved millions of animals that would otherwise have died from rabies, distemper, feline leukemia, infectious hepatitis virus, tetanus, anthrax, and canine parvo virus. Treatments for animals developed using animal testing also include pacemakers for heart disease and remedies for glaucoma and hip dysplasia. [ 9 ] [ 21 ] Animal testing has also been instrumental in saving endangered species from extinction, including the black-footed ferret, the California condor and the tamarins of Brazil. The American Veterinary Medical Association (AVMA) endorses animal testing to develop safe drugs, vaccines, and medical devices. [ 9 ] [ 13 ] [ 23 ] Read More

Pro 2 Animals are appropriate research subjects because they are similar to human beings in many ways. Chimpanzees share 99% of their DNA with humans, and mice are 98% genetically similar to humans. All mammals, including humans, are descended from common ancestors, and all have the same set of organs (heart, kidneys, lungs, etc.) that function in essentially the same way with the help of a bloodstream and central nervous system. Because animals and humans are so biologically similar, they are susceptible to many of the same conditions and illnesses, including heart disease, cancer, and diabetes. [ 9 ] [ 17 ] [ 18 ] Animals often make better research subjects than humans because of their shorter life cycles. Laboratory mice, for example, live for only two to three years, so researchers can study the effects of treatments or genetic manipulation over a whole lifespan, or across several generations, which would be infeasible using human subjects. Mice and rats are particularly well-suited to long-term cancer research, partly because of their short lifespans. [ 9 ] [ 29 ] [ 30 ] Further, animals must be used in cases when ethical considerations prevent the use of human subjects. When testing medicines for potential toxicity, the lives of human volunteers should not be put in danger unnecessarily. It would be unethical to perform invasive experimental procedures on human beings before the methods have been tested on animals, and some experiments involve genetic manipulation that would be unacceptable to impose on human subjects before animal testing. The World Medical Association Declaration of Helsinki states that human trials should be preceded by tests on animals. [ 19 ] [ 20 ] A poll of 3,748 scientists by the Pew Research Center found that 89% favored the use of animals in scientific research. The American Cancer Society, American Physiological Society, National Association for Biomedical Research, American Heart Association, and the Society of Toxicology all advocate the use of animals in scientific research. [ 36 ] [ 37 ] [ 38 ] [ 39 ] [ 40 ] [ 120 ] Read More

Pro 3 Animal research is highly regulated, with laws in place to protect animals from mistreatment. In addition to local and state laws and guidelines, animal research has been regulated by the federal Animal Welfare Act (AWA) since 1966. As well as stipulating minimum housing standards for research animals (enclosure size, temperature, access to clean food and water, and others), the AWA also requires regular inspections by veterinarians. [ 3 ] All proposals to use animals for research must be approved by an Institutional Animal Care and Use Committee (IACUC) set up by each research facility. Most major research institutions’ programs are voluntarily reviewed for humane practices by the Association for Assessment and Accreditation of Laboratory Animal Care International (AAALAC). [ 24 ] [ 25 ] Animal researchers treat animals humanely, both for the animals’ sake and to ensure reliable test results. Research animals are cared for by veterinarians, husbandry specialists, and animal health technicians to ensure their well-being and more accurate findings. Rachel Rubino, attending veterinarian and director of the animal facility at Cold Springs Harbor Laboratory, says, “Most people who work with research animals love those animals…. We want to give them the best lives possible, treat them humanely.” At Cedars-Sinai Medical Center’s animal research facility, dogs are given exercise breaks twice daily to socialize with their caretakers and other dogs, and a “toy rotation program” provides opportunities for play. [ 28 ] [ 32 ] Read More

Con 1 Animal testing is cruel and inhumane. Animals used in experiments are commonly subjected to force feeding, food and water deprivation, the infliction of burns and other wounds to study the healing process, the infliction of pain to study its effects and remedies, and “killing by carbon dioxide asphyxiation, neck-breaking, decapitation, or other means,” according to Humane Society International. The US Department of Agriculture reported in Jan. 2020 that research facilities used over 300,000 animals in activities involving pain in just one year. [ 47 ] [ 102 ] Plus, most experiments involving animals are flawed, wasting the lives of the animal subjects. A peer-reviewed study found serious flaws in the majority of publicly funded US and UK animal studies using rodents and primates: “only 59% of the studies stated the hypothesis or objective of the study and the number and characteristics of the animals used.” A 2017 study found further flaws in animal studies, including “incorrect data interpretation, unforeseen technical issues, incorrectly constituted (or absent) control groups, selective data reporting, inadequate or varying software systems, and blatant fraud.” [ 64 ] [ 128 ] Only 5% of animals used in experiments are protected by US law. The Animal Welfare Act (AWA) does not apply to rats, mice, fish, and birds, which account for 95% of the animals used in research. The types of animals covered by the AWA account for fewer than one million animals used in research facilities each year, which leaves around 25 million other animals without protection from mistreatment. The US Department of Agriculture, which inspects facilities for AWA compliance, compiles annual statistics on animal testing but they only include data on the small percentage of animals subject to the Act. [ 1 ] [ 2 ] [ 26 ] [ 28 ] [ 135 ] Even the animals protected by the AWA are mistreated. Violations of the Animal Welfare Act at the federally funded New Iberia Research Center (NIRC) in Louisiana included maltreatment of primates who were suffering such severe psychological stress that they engaged in self-mutilation, infant primates awake and alert during painful experiments, and chimpanzees being intimidated and shot with a dart gun. [ 68 ] Read More

Con 2 Animal tests do not reliably predict results in human beings. 94% of drugs that pass animal tests fail in human clinical trials. Over 100 stroke drugs and over 85 HIV vaccines failed in humans after succeeding in animal trials. Nearly 150 clinical trials (human tests) of treatments to reduce inflammation in critically ill patients have been undertaken, and all of them failed, despite being successful in animal tests. [ 57 ] [ 58 ] [ 59 ] Drugs that pass animal tests are not necessarily safe. The 1950s sleeping pill thalidomide, which caused 10,000 babies to be born with severe deformities, was tested on animals prior to its commercial release. Later tests on pregnant mice, rats, guinea pigs, cats, and hamsters did not result in birth defects unless the drug was administered at extremely high doses. Animal tests on the arthritis drug Vioxx showed that it had a protective effect on the hearts of mice, yet the drug went on to cause more than 27,000 heart attacks and sudden cardiac deaths before being pulled from the market. [ 5 ] [ 55 ] [ 56 ] [ 109 ] [ 110 ] Plus, animal tests may mislead researchers into ignoring potential cures and treatments. Some chemicals that are ineffective on (or harmful to) animals prove valuable when used by humans. Aspirin, for example, is dangerous for some animal species. Intravenous vitamin C has shown to be effective in treating sepsis in humans, but makes no difference to mice. Fk-506 (tacrolimus), used to lower the risk of organ transplant rejection, was “almost shelved” because of animal test results, according to neurologist Aysha Akhtar. A report on Slate.com stated that a “source of human suffering may be the dozens of promising drugs that get shelved when they cause problems in animals that may not be relevant for humans.” [ 105 ] [ 106 ] [ 127 ] Read More

Con 3 Alternative testing methods now exist that can replace the need for animals. Other research methods such as in vitro testing (tests done on human cells or tissue in a petri dish) offer opportunities to reduce or replace animal testing. Technological advancements in 3D printing allow the possibility for tissue bioprinting: a French company is working to bioprint a liver that can test the toxicity of a drug. Artificial human skin, such as the commercially available products EpiDerm and ThinCert, can be made from sheets of human skin cells grown in test tubes or plastic wells and may produce more useful results than testing chemicals on animal skin. [ 15 ] [ 16 ] [ 50 ] [ 51 ] Michael Bachelor, Senior Scientist and Product Manager at biotech company MatTek, stated, “We can now create a model from human skin cells — keratinocytes — and produce normal skin or even a model that mimics a skin disease like psoriasis. Or we can use human pigment-producing cells — melanocytes — to create a pigmented skin model that is similar to human skin from different ethnicities. You can’t do that on a mouse or a rabbit.” The Environmental Protection Agency is so confident in alternatives that the agency intends to reduce chemical testing on mammals 30% by 2025 and end it altogether by 2035. [ 61 ] [ 134 ] [ 140 ] Scientists are also able to test vaccines on humans volunteers. Unlike animals used for research, humans are able to give consent to be used in testing and are a viable option when the need arises. The COVID-19 (coronavirus) global pandemic demonstrated that researchers can skip animal testing and go straight to observing how vaccines work in humans. One company working on a COVID-19 vaccine, Moderna Therapeutics, worked on developing a vaccine using new technology: instead of being based on a weakened form of the virus, it was developed using a synthetic copy of the COVID-19 genetic code. [ 142 ] [ 143 ] Read More

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Animal testing and experiments FAQ

How many animals are used in experiments each year?

Which animals are used in experiments, what kinds of experiments are animals used in, what kinds of institutions use animals in experiments, where do laboratories get the animals they use in experiments, what is life like for animals in laboratories, what happens to the animals once an experiment is over, aren’t there laws to protect animals used in experiments, why are animals still used in experiments, what are the alternatives to experiments on animals, what are the advantages of using non-animal alternatives instead of animals in experiments.

• What are you doing to end experiments on animals?

What can I do to help animals in laboratories?

Stand with us to demand that the federal government, state governments, companies and universities stop relying on outdated animal experiments.

It is estimated that more than 50 million animals are used in experiments each year in the United States. Unfortunately, no accurate figures are available to determine precisely how many animals are used in experiments in the U.S. or worldwide.

The U.S. Department of Agriculture (USDA) does compile annual statistics on some animals used in experiments, including cats , dogs , guinea pigs , hamsters , pigs , primates , rabbits and  sheep .

However, the animals most commonly used in experiments—“purpose-bred” mice and rats  (mice and rats bred specifically to be used in experiments)—are not counted in annual USDA statistics and are not afforded the minimal protections provided by the Animal Welfare Act. The Animal Welfare Act is a federal law that sets minimal standards for the treatment of certain warm-blooded animals used in experiments. The law also requires that unannounced inspections of all regulated animal testing facilities are carried out annually, although some facilities only receive partial inspections . In addition to purpose-bred mice and rats, animals such as crabs, fish , frogs, octopuses and turtles , as well as purpose-bred birds , are not covered by the Animal Welfare Act. The failure to protect these animals under the law means that there is no oversight or scrutiny of their treatment in the laboratory or the experiments performed on them. And, because these animals are not counted, no one knows how many of them are suffering in laboratories. It also means that facilities using unprotected species in experiments are not required to search for alternative, non-animal methods that could be used to replace or reduce harmful experiments that use animals.

View Animals Used in Experiments by State

View Dogs Used in Experiments by State

Read Dogs Used in Experiments FAQ

Use our Animal Laboratory Search Tool  to find information about universities, hospitals, companies and other organizations that use certain animals in experiments

View a list of U.S. laboratories that use certain animals in experiments ; click on “License Type” and select “Class R – Research Facilities." Note that numbers only include animals covered by the Animal Welfare Act.

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Animals used in experiments include baboons, cats , cows , dogs , ferrets,  fish , frogs, guinea pigs , hamsters , horses , llamas, mice , monkeys (such as marmosets and macaques), owls, pigs , quail, rabbits , rats and  sheep .

Chimpanzees have thankfully not been subjected to invasive experiments in the U.S. since 2015, when federal decisions were made to prevent their use. Despite this, hundreds of chimpanzees are still languishing in laboratories while they wait to be moved to sanctuaries.

Animals are used in many different kinds of experiments. These are just a few examples:

• Dogs have their hearts, lungs or kidneys deliberately damaged or removed to study how experimental substances might affect human organ function.  
• Monkeys are taken from their mothers as infants to study how extreme stress might affect human behavior.
• Mice are force-fed daily doses of a chemical for two years to see if it might cause cancer in humans.
• Cats have their spinal cords damaged and are forced to run on treadmills to study how nerve activity might affect human limb movement.
• Ferrets are deliberately infected with extremely painful, potentially fatal diseases (such as RSV, COVID-19 or Ebola) and not given pain relief or treatment before their death to study how humans might be affected by the same disease.  
• Pigs are implanted with various devices (such as pacemakers and dental implants) to study how human bodies might respond to such devices.  
• Pregnant rabbits are force-fed toxic pesticides every day for several weeks to study how human mothers and babies might be affected if they were exposed to the pesticides.
• Sheep are subjected to high pressures (such as those experienced deep underwater) for hours at a time and then returned to normal pressure so that their response can be observed.
• Rats are placed in small tubes and are forced to inhale cigarette smoke for hours at a time to study how humans might respond to cigarette smoke.   
• Baboons are injected with endometrial tissue to induce painful symptoms of endometriosis and study how humans might be affected by the disorder.
• Horses are infected with a potentially fatal virus (such as hepatitis) and their symptoms monitored to study how humans might be affected by the same virus.

Experiments are often excruciatingly painful for the animals used and can vary in duration from days to months to years. The experiment can cause vomiting, diarrhea, irritation, rashes, bleeding, loss of appetite, weight loss, convulsions, respiratory distress, salivation, paralysis, lethargy, bleeding, organ abnormalities, tumors, heart failure, liver disease, cancer and death.

There is no limit to the extent of pain and suffering that can be inflicted on animals during experiments. In some instances, animals are not given any kind of pain medication to help relieve their suffering or distress during or after the experiment on the basis that it could affect the experiment.

Animals are typically killed once an experiment is over so that their tissues and organs can be examined, although it is not unusual for animals to be used in multiple experiments over many years. There are no accurate statistics available on how many animals are killed in laboratories every year.

Read Cosmetics Animal Testing FAQ

• Read about our 2022 undercover investigation at Indiana laboratory Inotiv, one of America’s largest animal testing labs. We documented hundreds of dogs, monkeys, rats and pigs undergoing experiments, including terrified beagle puppies being force-fed a potentially toxic drug in cruel and ineffective months-long tests paid for by Crinetics, a pharmaceutical company in San Diego.
• Read about our 2019 undercover investigation at a Michigan laboratory where thousands of dogs are killed every year. After weeks of pressure from the public, the pesticide company that had commissioned a year-long fungicide test on 32 dogs agreed that the test was unnecessary and released the dogs to one of our shelter partners to be adopted.

Chemical, pesticide and drug companies (as well as contract laboratories that carry out tests for those companies), public and private universities, community and technical schools, government facilities, Veterans Affairs (VA) facilities and hospitals all use animals in experiments.

View USDA List of Organizations that Use Dogs in Experiments

View Chart of Institutions That Use Dogs in Experiments

The majority of animals in laboratories are “purpose-bred” meaning that they are bred specifically to be used in experiments. People who breed and sell certain purpose-bred animals are called Class A dealers and are licensed and inspected by the U.S. Department of Agriculture (USDA). Facilities that only sell purpose-bred mice, rats, birds or cold-blooded animals such as crabs, fish, frogs, octopuses and turtles to laboratories are excluded and are not licensed or inspected by the USDA.

Some animals used in experiments are taken from the wild—including birds and  monkeys . 

Historically, some cats and dogs  were sold to laboratories by brokers known as random source Class B dealers, who acquired animals at auctions, from newspaper ads and various other sources, including animal shelters. Random source Class B dealers have not been allowed to operate since 2015 when Congress first passed legislation to prevent them from being licensed.  

Some cats and dogs in laboratories are still obtained directly from animal shelters, a practice known as “pound seizure.” Pound seizure laws vary from state to state with one state (Oklahoma) requiring shelters to give cats and dogs to laboratories, rather than euthanizing them, and others allowing or prohibiting laboratories from taking animals from animal shelters. Some states have no laws at all, leaving it up to the individual shelter or locality.

View Pound Seizure Laws by State

Animals in laboratories suffer immensely. In addition to the painful experiments that the vast majority of animals in laboratories experience over days, months, years or even decades, life in a laboratory is typically a miserable and terrifying experience.

Typically kept alone in barren steel cages with little room to move around and few, if any, comforts, such as toys or soft bedding, animals often become excruciatingly lonelyand anxious, often devoid of the companionship of other animals or the loving touch of a human. Animals in laboratories can associate humans with painful situations and, with no way to hide or get away, they panic whenever a person approaches their cage or freeze with fear when they are taken into treatment rooms. Despite this, dogswill often still seek out human attention.

Animals in laboratories typically also have to watch (or hear) other animals suffering, including their own parents, siblings or babies. High levels of constant stress can cause animals to exhibit unnatural behaviors. For example, it is not uncommon for monkeys to mutilate themselves or to rock or vocalize constantly as a way to help relieve their anxiety, mice to overgroom each other until they are completely bald, and dogs to continually pace.  

Very often the experiments themselves lead to suffering and death. In our 2022 undercover investigation we documented monkeys in “restraint chairs”—devices that are used to hold monkeys in place while the experiments are carried out—who accidentally hanged themselves while unattended. We also documented a dog named Riley used to test a substance so toxic that it brought him near death after only two days of forced dosing. He was hypersalivating, trembling, vomiting, and moaning, yet was dosed yet again with this highly toxic substance. Later, he lay on the floor, unable to stand. Our undercover investigator tried to comfort him while he was dying, but Riley was left to suffer in excruciating pain overnight because the laboratory’s veterinarian was unavailable on a weekend

Animals in laboratories are also subject to mistreatment by inexperienced or careless staff. Although there are penalties for laboratories when animals are injured or killed due to negligence or when they fail to meet minimum standards of animal care, in reality, the fines are typically either very small or waived entirely.

In some cases, animals die as a deliberate result of the experiment. For example, the LD50 (lethal dose 50%) test, which is typically performed on mice, rats, pigeons, quail and fish, involves determining the dose of a substance (such as a pesticide) that kills (or would lead to the death of) 50% of the animals tested.

It is extremely rare that animals are either adopted out or placed into a sanctuary after research is conducted on them. However, more and more states are passing laws that require laboratories, when possible, to offer dogs and cats to shelters and other rescue organizations so they can be adopted into loving homes after the experiments they were used in have ended. As of December 2023, 16 states have such laws.

The Animal Welfare Act was designed to protect certain animals, like dogs and monkeys, used in experiments, but the law only offers minimal standards for housing, food and exercise. The Animal Welfare Act also stipulates that the proposed experiments be reviewed by an Institutional Animal Care and Use Committee, whose members are appointed by the laboratory itself and largely made up of employees of the institution. A 2014 audit report reviewing Animal Welfare Act oversight of laboratories found that “animals are not always receiving basic humane care and treatment and, in some cases, pain and distress are not minimized during and after experimental procedures.”

The animals most commonly used in experiments—“purpose-bred” mice and rats  (mice and rats bred specifically to be used in experiments)—are not counted in annual USDA statistics and are not afforded the minimal protections provided under the Animal Welfare Act. The Animal Welfare Act is a federal law that sets minimal standards for the treatment of certain warm-blooded animals used in experiments. The law also requires that unannounced inspections of all regulated research facilities are carried out annually. In addition to purpose-bred mice and rats, animals such as crabs, fish , frogs, octopuses and turtles as well as purpose-bred birds are not covered by the Animal Welfare Act. The failure to protect these animals under the law means that there is no oversight or scrutiny of their treatment and use in the laboratory. And, because these animals are not counted, no one knows how many of them are suffering in laboratories. It also means that facilities using unprotected species in experiments are not required to search for alternative, non-animal methods that could be used to replace or reduce harmful experiments that use animals.

The vast majority of experiments on animals are not required by government law or regulations. Despite that, government agencies often seem to prefer that companies carry out animal tests to assess the toxicity or efficacy of products such as industrial chemicals, pesticides, medical devices and medicines.

For example, the Environmental Protection Agency (EPA) requires that a new pesticide be fed to dogs for 90 days as part of its evaluation and approval process. The Food and Drug Administration (FDA), which regulates various products such as drugs, medical devices, food, fragrances and color additives, will not approve potential drugs unless they are first tested on animals, which usually includes dogs. In addition to tests on  dogs ,  mice and rats ,  rabbits ,  birds  and primates are also used to test pesticides and drugs. These types of tests have been performed for years, regardless of whether they provide valuable information. While some regulatory agencies, like the EPA, are now taking a critical look at these animal tests to determine if they provide information necessary for assessing how safe a product or substance is for humans, and if better approaches are available, others have done little. More efforts can be made by agencies to invest in and encourage the development of non-animal methods.

Swapping animal experiments for non-animal alternative methods seems like a straightforward process, given that using animals has so many limitations and sophisticated new technologies offer countless possibilities for creating methods that are more humane and that more accurately mimic how the human body will respond to drugs, chemicals or treatments. Unfortunately, developing these alternatives is a complex process facing many obstacles, including inadequate funding. In most cases, a non-animal alternative must be formally validated—historically an expensive and lengthy process—in order to be accepted by government regulatory agencies, both in the U.S. and globally, although new, faster approaches to approving these methods are being developed. In contrast, animal experiments have never been subjected to the same level of scrutiny and validation. Despite these challenges, many scientists are increasingly committed to developing and using non-animal methods.

The world is continuously moving toward a future dominated by sophisticated methods that use human cells, tissues and organs, 3D printing, robotics, computer models and other technologies to create experiments that do not rely on animals.

While many animal experiments have not changed since they were developed decades ago and will always have severe limitations, advanced non-animal methods represent the very latest techniques that science has to offer, provide countless possibilities to improve our understanding and treatment of human diseases and will only continue to improve over time. Non-animal methods also have several advantages over outdated animal experiments: they more closely mimic how the human body responds to drugs, chemicals and treatments; they are more efficient and often less expensive; and they are more humane. Ultimately, moving away from animal experiments is better for both humans and animals.

We advocate for the immediate replacement of animal experiments with available non-animal methods and for more funding to develop new non-animal methods. A concerted effort to shift funding and technological development toward more non-animal alternatives will lead us to a future where animal experiments are a thing of the past.

Examples of non-animal alternative methods

• “Organs-on-chips” are tiny 3D chips created from human cells that look and function like miniature human organs. Organs-on-chips are used to determine how human systems respond to different drugs or chemicals and to find out exactly what happens during infection or disease. Several organs, representing heart, liver, lungs or kidneys, for example, can be linked together through a “microfluidic” circulatory system to create an integrated “human-on-a-chip” model that lets researchers assess multi-organ responses.
• Sophisticated computer models use existing information (instead of carrying out more animal tests) to predict how a medicine or chemical, such as drain cleaner or lawn fertilizer, might affect a human.
• Cells from a cancer patient’s tumor are used to test different drugs and dosages to get exactly the right treatment for that specific individual, rather than testing the drugs on animals.
• Specialized computers use human cells to print 3D tissues that are used to test drugs.
• Skin cells from patients, such as those with Alzheimer’s disease, are turned into other types of cells (brain, heart, lung, etc.) in the laboratory and used to test new treatments.
• Sophisticated computer programming, combined with 3D imaging, is used to develop highly accurate 3D models of human organs, such as the heart. Researchers then input real-world data from healthy people and those with heart disease to make the model hearts “beat” and test how they might respond to new drugs.

Human cells or synthetic alternatives can replace horseshoe crab blood in tests to determine whether bacterial contaminants are present in vaccines or injectable drugs.

• Animal experiments are time-consuming and expensive.
• Animal experiments don’t accurately mimic how the human body and human diseases respond to drugs, chemicals or treatments.
• Animals are very different from humans and, therefore, react differently.
• Increasing numbers of people find animal testing unethical.
• There are many diseases that humans get that animals do not.

What are you doing to end experiments on animals?

We advocate for replacing animals with non-animal alternative methods when they are available and more funding for the development of new alternative methods to quickly replace antiquated and unreliable animal tests and experiments. Our two main areas of focus are ending cosmetics animal testing  and ending experiments on dogs .

Cosmetics testing on animals

We—along with our partner, Humane Society International —are committed to ending cosmetics animal testing forever. Through our  Be Cruelty-Free campaign, we are working in the United States and around the globe to create a world where animals no longer have to suffer to produce lipstick and shampoo. 

• In the United States, we are working to pass the Humane Cosmetics Act , federal legislation that would prohibit animal testing for cosmetics, as well as the sale of animal-tested cosmetics.
• We are also working in several U.S. states to pass legislation that would end cosmetics animal testing. As of March 2024, 12 states (California, Hawai'i, Illinois, Louisiana, Maine, Maryland, Nevada, New Jersey, New York, Oregon, Virginia and Washington) have passed laws banning the sale of animal-tested cosmetics.
• Internationally, as of December 2023, 45 countries have passed laws or regulations to ban cosmetics animal testing, including every country in the European Union, Australia, Brazil, Canada, Chile, Colombia, Ecuador, Guatemala, Iceland, India, Israel, Mexico, New Zealand, Norway, South Korea, Switzerland, Taiwan, Turkey, the United Kingdom.
• We work with scientists from universities, private companies and government agencies around the globe to promote the development, use and regulatory acceptance of non-animal test methods that will reach beyond cosmetics.
• We educate consumers about animals used in cruel and unnecessary cosmetics tests and how to shop for cruelty-free cosmetics and personal care products.

Experiments on dogs

There is no place for harmful experiments on dogs in the U.S. We are committed to ending this practice.

• In the summer of 2022, we led the removal of 3,776 beagles from Envigo, a facility in Virginia that bred dogs to sell to animal laboratories. This historic mission was the result of a lawsuit filed by the U.S. Department of Justice that described shocking violations of the Animal Welfare Act at the facility. Instead of continuing to suffer, the dogs were removed from Envigo and headed to loving homes , a process facilitated by our shelter and rescue partners around the country.
• In April 2022, we released the results of our undercover investigation at Inotiv, an Indiana laboratory where thousands of dogs, monkeys, pigs and rats are used in experiments and killed.
• In 2021, we released a report examining the U.S. government’s role in using dogs in experiments. We found that the government uses millions of taxpayer dollars to fund harmful experiments on dogs each year—and also seems to prefer that companies carry out dog tests. Our researchers scrutinized public records and found that between 2015 and 2019, the National Institutes of Health (NIH) awarded more than $200 million to 200 institutions for 303 projects that used dogs in harmful experiments. Dogs were subjected to multiple surgeries, fitted with equipment to impair their heart function and implanted with devices to alter normal bodily functions. Following the conclusion of an experiment, dogs are typically killed instead of being adopted into loving homes.
• In 2019, we released the results of our undercover investigation at a Michigan laboratory where thousands of dogs are killed every year. After weeks of pressure from the public, the pesticide company that had commissioned a test year-long fungicide test on 32 dogs, agreed that the test was unnecessary and released the dogs to one of our shelter partners so they could be adopted.
• After a recent analysis we performed that showed the 90-day dog test for pesticide registration was rarely used by the Environmental Protection Agency (EPA) to assess the risk that pesticides pose to humans, we are urging the agency to eliminate or significantly limit this test in the near future. We also want the agency to reaffirm their previously stated commitment to end their reliance on using mammals to test pesticides and chemicals by 2035.
• We are asking the Food and Drug Administration (FDA) to support the development of alternative methods that replace dogs in experiments. 
• We want the Department of Veterans Affairs (VA) to adopt the recommendations of an independent panel review released in 2020 that analyzed VA experiments using dogs, identified several areas where dogs are not needed and urged the agency to develop a strategy to replace all animal use. 
• We are recommending that the National Institutes of Health (NIH) scrutinize grant proposals for projects using dogs, by applying strict criteria that must be met before dogs can be used and that they ban the use of dogs in experiments that cause unrelieved pain. We are also requesting that the NIH define a date when they will no longer fund or support experiments on dogs.
• prohibit or limit the use of dogs in experiments not required by federal law, similar to laws passed in California and Illinois .
• ensure an opportunity for  dogs and cats to be adopted into loving homes after the experiment ends.
• strengthen regulatory oversight of facilities that breed dogs destined for laboratories and increase penalties for animal welfare violations.
• Direct state funding to support the research and development of modern non-animal technologies, similar to the law passed in Maryland .

One easy way to help animals suffering in cosmetics tests is to swap out your personal care and household products for cruelty-free versions! Cosmetics (such as shampoo, deodorant and lipstick) and household products (such as dish soap, laundry detergent and glass cleaner) are typically tested on guinea pigs , rabbits ,  mice and rats .

Help us demand better for animals used in experiments through the following actions:

• Tell the FDA to stop encouraging companies to test on animals and instead switch to sophisticated non-animal alternatives.
• Stand with us to end research and tests on dogs by signing our petition.
• Urge the USDA to do their job and help protect animals in laboratories.
• Ask your federal legislators in Congress to ban cosmetic tests on animals.
• Support efforts to replace animal experiments with advanced non-animal alternatives that are better for both human health and animal welfare.

Follow us on Facebook to learn the latest news and actions related to animals in laboratories!

Alternatives to horseshoe crab blood

The Humane Society of the United States urges that horseshoe crab blood be replaced with non-animal methods when conducting endotoxin tests for medical products.

Vaccine, injectable drug and medical device manufacturers must test for endotoxins, a type of bacterial contaminant that, if present, can cause patients to develop symptoms that can include fever, chills, headache and nausea. Blood from horseshoe crabs is used to conduct the Limulus amebocyte lysate (or LAL) test for endotoxins.

The problem

To create this test, horseshoe crabs are captured from the wild and up to 30% of their blood is removed by medical supply companies. The crabs are later returned to the wild; however, it is estimated that 10-15% or more of them die as a result of this process.

In addition to being collected for their blood, horseshoe crabs are gathered up by fisheries, which use them as bait. These practices have led to a rapid decrease in the horseshoe crab population, putting them at risk of extinction. The decrease in wild horseshoe crab populations also impacts other species, including migratory shorebirds like the red knot, a threatened species that depends on horseshoe crab eggs for food.

THE solution

Scientists have developed recombinant Factor C (rFC), a synthetic alternative to the protein in horseshoe crab blood that can detect bacterial endotoxins. Repeated studies have demonstrated that rFC is equivalent or superior to the LAL test. A second method—the monocyte activation test—uses human cells and can not only detect bacterial endotoxins, but also pyrogenic (fever-causing) non-endotoxins.

what should be done

As a member of the Horseshoe Crab Recovery Coalition, the Humane Society of the United States is advocating for the replacement of the Limulus amebocyte lysate test with recombinant Factor C (rFC) or the monocyte activation test (MAT).

We urge the U.S. Pharmacopoeia—which sets quality, purity, strength and identity standards for medicines, food ingredients and dietary supplements—to encourage manufacturers to use rFC or MAT rather than LAL.

We also urge the U.S. Food and Drug Administration to update its guidance for vaccine, injectable drug and device manufacturers to indicate that these non-animal tests are now the preferred methods for endotoxin and pyrogenicity testing.

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The "Pit Of Despair" Was One Of The Most Unethical Experiments Of Modern Science

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Over the course of his career, Harry Harlow's experiments earned him both academic acclaim and public notoriety. Image credit: deanmoriarty44/Shutterstock.com

In a quest to understand the nature of depression and loneliness, an influential scientist in the late-1960s designed a scientific apparatus that’s more akin to a monkey torture device.

The Pit Of Despair

The experiment was developed by American psychologist Harry Harlow with the hopes of producing an animal model of depression to better understand the condition and potentially find possible treatments. A rhesus macaque monkey would be placed into a large vertical cone-shaped structure fashioned out of hard, cold stainless steel. The floor of the device was made from wire-mesh, allowing poop to drop out of the bottom. Within this "pit," the monkeys would be fed and given water, but ultimately left alone for weeks at a time.

Harlow named this device the “pit of despair.” As he explains in a 1969 paper [ PDF ], the idea was to reflect the emotional sensation felt by a human with severe depression: “Depressed human beings report that they are in the depths of despair or sunk in a well of loneliness and hopelessness. Therefore we built an instrument that would meet these criteria and euphemistically called it the pit, or the vertical chamber for those who find the term ‘pit’ psychologically unacceptable.”

Most monkeys would fall into a still and huddled state within a matter of days of being placed in the pit. Once removed from the device, the monkeys would not revert back to normal social behavior. Harlow explains in a 1971 study that monkeys subjected to the “pit of despair” for 30 days would not play, shied away from social interaction, and showed no signs of curiosity. The majority of the monkeys would simply remain still in a huddle position, clasping their own body with their hands. These "profound behavioral anomalies," in Harlow's words, would remain even months after being freed from the device. 

While Harlow argued that the device held "enormous potential” for the study of depression, it is unclear whether this particular avenue of research ever provided any real insights into clinical depression or offered any possible ways to treat it. 

Harry Harlow

Over the course of his lengthy career, which spanned from the 1930s right up to the 1970s, Harry Harlow achieved both academic acclaim and public notoriety. 

Born in 1905, he spent most of his working life at the University of Wisconsin–Madison where enjoyed a great amount of success in his career. Harlow remains one of the most cited psychologists of the 20th century, but his work has aroused more than its fair share of controversy, for obvious reasons.

Using macaques as his subject, he showed how parental bonds, caregiving, and companionship (what some might call “love”) in early life were hugely important for social and cognitive development. He also highlighted how an infant has a profound psychological yearning for affection with a parental figure that goes much deeper than a utilitarian desire for warmth, protection, and food.

Before Harlow, scientists and academics in the first half of the 20th century  pushed the idea that parents should keep emotionally distant from their own children. To condition an individual to become a well-rounded adult, they believed crying babies should be left alone and ignored, rather than responded to. One prominent child psychologist even told parents to not kiss their children goodnight, but give them a nice firm handshake before bed.  Harlow was one of the many prominent figures to challenge this paradigm. 

Towards the end of his career, Harlow's interests veered towards the scientific investigation of depression.  It’s been said that he was driven to understand the condition due to his own experience with severe depression, which intensified following his wife’s death in 1971. He died in 1981, plagued by depression and alcoholism.

The Ethics of Animal Testing

To most, Harlow’s experiments were sadistic, unjustified, and exploitative. In the words of American literary critic Wayne C Booth: "Harry Harlow and his colleagues go on torturing their nonhuman primates decade after decade, invariably proving what we all knew in advance—that social creatures can be destroyed by destroying their social ties."

Harlow did not exactly shy away from this image of a cold-hearted experimenter, either. In a 1974 interview, he reportedly remarked: “The only thing I care about is whether the monkeys will turn out a property I can publish. I don't have any love for them. Never have. I really don't like animals. I despise cats, I hate dogs. How could you like a monkey?” 

Some have hinted that Harlow appeared to have taken pleasure in giving his devices vivid and purposely shocking names. Along with the “pit of despair,” he also created the "tunnel of terror," "the iron maiden," — named after a literal torture device — and "rape racks" — a device that forced female monkeys to have sex.

Clearly, PR was not his strong point. 

Nevertheless, Harlow  continues to influence the way we see child development and helped to  reshape orphanages, adoptions services, and child care in the latter half of the 20th century. Some have even argued that Harlow's work forced the scientific world to rethink the use of animals in research.

Certainly, his experiments would struggle to get past a university's ethics committee in the 21st century, but animal experimentation continues to be widely used in scientific research. According to statistics from the US Department of Agriculture, scientists in the US used 75,825 non-human primates for research in 2018.

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13.7 Cosmos & Culture

The 'necessity' of animal research does not mean it's ethical.

Samual Garner

Diane, a 4-year-old chimpanzee, relaxes in the trees at the Chimp Haven sanctuary in Keithville, La., on Aug. 25, 2014. She is one of many chimps who have been moved here from the New Iberia Research Center in Lafayette, La. Brandon Wade/AP hide caption

Diane, a 4-year-old chimpanzee, relaxes in the trees at the Chimp Haven sanctuary in Keithville, La., on Aug. 25, 2014. She is one of many chimps who have been moved here from the New Iberia Research Center in Lafayette, La.

A few weeks ago, two prominent scientists, Hollis Cline and Mar Sanchez, wrote a brief piece in The Hill newspaper arguing that animal research is "necessary." They were prompted by the recent National Institutes of Health (NIH) decision to phase out the use of primates in controversial maternal deprivation studies.

Scientists have long been fond of claims of necessity — in fact, justifications for animal research have remained largely the same since the writings of 19th century French physiologist Claude Bernard. However, this claim is problematic for a number of reasons.

If animal research is necessary, then it is not necessary in the sense that we have to do it. Rather, it is a choice that we make, a choice that its proponents believe is a necessary means to the end of further medical advances. Such advances are undoubtedly of significant moral importance, but even if we grant the assumption that animals are necessary for medical progress, this does not equate to a moral justification.

Research with humans is necessary to medical progress, but we have set strict limits on the extent to which humans can be exposed to risk and harm in research, even though doing so has undoubtedly slowed the rate of medical progress that might otherwise be achievable. Cline and Sanchez claim that animals in research are treated "humanely and with dignity," but the reality is that the level of protection afforded to research animals is far, far less than that afforded to human participants in research. Most animals involved in research are killed at the termination of the experiment, are kept in conditions not conducive to their welfare, and are otherwise harmed in myriad and significant ways, for example through the infliction of physical injuries, infectious diseases, cancers, or psychological distress.

While nonhuman animals cannot provide consent to research participation, we have reasoned in the case of humans that an inability to consent entitles an individual to greater protection and not lesser protection. What justifies our differential treatment of humans and nonhuman animals in research? For present purposes, it isn't necessary to rehearse every possible argument for and against animal research. It is sufficient to note that very few contemporary ethicists defend the status quo of animal research and, furthermore, that the burden of proof has now shifted to those who would defend invasive animal research.

Given the state of philosophical scholarship, meeting this burden of proof will not be easy or straightforward. Perhaps the most remarkable aspect of the scientific community's frequent claims of the necessity of animal research is how thoroughly they miss the moral point. For the most part, ethical criticisms of animal research aren't even addressed — as they aren't in Cline and Sanchez's piece — and when they are, they're usually dismissed with bad arguments, like this one , that have been refuted for decades.

Further, the claim that "animal research is necessary to medical progress" assumes a strong causal connection between the two, but what data we have available cast doubt upon the robustness of this connection. Despite strong claims about the historical benefits of animal research from the scientific community, the accuracy of animal models in predicting human responses has not been evaluated sufficiently, and the lack of certain kinds of data make this evaluation especially challenging . Based on existing data, however, numerous reviews have suggested that the accuracy of animal research in predicting human health outcomes appears to be far less than what we once assumed.

Animal studies also frequently appear to be poorly designed . The predictive value of animal research might increase if study design improved, but this isn't certain. Even NIH Director Francis Collins recognized these concerns in a forward-thinking 2011 commentary , stating that, "The use of animal models for therapeutic development and target validation...may not accurately predict efficacy in humans." Given these issues, systematic reviews should become routine and strong statements about the utility of animal models should be tempered. This does not mean that animal research has never produced any or even many important medical benefits, but these claims require empirical validation, not simply repeated assertion.

It also means that scientists and science agencies should be much more aggressive about seeking and funding alternatives to animals in research. Support has certainly grown, but investment of money and human labor into non-animal alternatives has been paltry. Even with this limited investment, some impressive advances are being made — witness the ongoing development of " organs on a chip " — but much more needs to be done, with more money behind it, and with more of a sense of haste.

Beyond funding, the scientific community simply needs to adopt a better attitude toward innovation in alternatives, or else their limitations will continue to be a self-fulfilling prophecy. This is science — a discipline with a remarkable history of achievement and innovation despite significant technical challenges. Where are the editorials galvanizing the scientific community to continue to innovate without animals? Where is the Human Genome Project-type investment in alternatives? To say that animal models are "necessary" when alternatives are not aggressively pursued seems a bit dishonest. And given the amount of harm caused to animals in research—whether you think it's justified or not—we should all want the alternatives field to grow.

Literally thousands of books and peer-reviewed papers have been written on the extent of our moral obligations to animals. As a field that is dedicated to rigorous inquiry and rational thought, the scientific community should take seriously the vast philosophy literature on these topics — the same field that gave rise to the conceptual foundations of science — rather than assertions and rhetoric. When it comes to animals and ethics, there have been very few serious attempts to engage the intellectual issues. Scientists can and should do better.

Samual Garner is a bioethicist living in Washington, DC. He is an associate fellow at the Oxford Centre for Animal Ethics and writes on human research ethics and animal ethics.

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Is animal research ethical?

Posted: by John Meredith on 16/02/22

More on these Topics:

How can it be right to use an animal for research where we could consider it unethical to use a human being? This is a fundamental question that confronts anybody who benefits from research using animals. If we claim that causing harm to animals is sometimes justifiable where it would be unacceptable to inflict a similar harm or risk on a person, then it seems we are assuming that animals must, in some sense, have less moral value. But is that a justifiable assumption, or is it just a self-serving prejudice? Are there solid rational arguments for treating humans differently from other animals, or are we simply falling back on outmoded habits of thought, a smokescreen that helps us avoid looking the ugly truth of our actions in the eye?

Moral status of animals

In the past, the moral status of animals did not merit a great deal of consideration; raising questions about whether humans were entitled to exploit animals would have struck most people as quaint or absurd. The great moral philosopher Rene Descartes, for example, the man famous for the phrase  cogito ergo sum  - ‘I think therefore I am’ - believed that animals had no inner life at all, that they were essentially as lifeless as clockwork dolls, incapable of emotion, self-awareness, or even feeling pain.  

Such ideas seem laughable to us now. We take it for granted that most animals experience pain and many have complex emotional lives that can depend on relationships with other animals and which can deliver feelings of pleasure and satisfaction. Since Descartes’ day, the growing study of animal behaviour makes this seem obvious, and cleverly designed experiments have confirmed what has been learned from observation, forcing us to acknowledge that sentience – inner life – exists in a great number of other species and sometimes at a very high level. 

But what implications does all this have for the moral consideration of animals? How should it affect the way we treat them? Philosopher Peter Singer, whose book  Animal Liberation  transformed the public debate on animal welfare, believes it should have deep and wide-reaching consequences. Singer argues that it is wrong to inflict harm on a person not because of any cosmic or biblical law about harm but because it is against that person’s interests as they themselves understand them. Considering moral questions in that light, he argues, explodes any idea that we can justify distinctions between individuals based on their sex or race, distinctions that have been passionately defended over many centuries. There are many differences between people of all kinds including, of course, both sexes, but they all have interests that are alike: an interest in avoiding pain or hunger for example. There is no rational basis for preferring the interests of any particular individual, or people of one race or sex class over those of another, that is simply racism and sexism. This is an idea has become widely accepted, if only recently, and it doesn’t seem particularly radical to us today, but Singer takes the idea a step further. 

If there is no non-arbitrary reason to prefer the interests of one human animal over another, how can there be any good reason to prefer the interests of a human animal over a non-human animal? Claims that humans are of special moral interest because of their intelligence or capacity for language or any of the many other things that have been suggested cut no ice.  A less intelligent human has as much interest in avoiding pain as a mathematical genius does, and the same goes for a dog, or a mouse, or a fish. To deny this, says Singer is to make a moral mistake akin to sexism or racism and he calls this way of thinking  speciesism .

One objection to the argument from speciesism is that it implies that there can never be a reason to prefer the welfare of a human being over any other animal where considerations of interest are the same. This strikes most people as counter-intuitive to say the least. Jean Kazez, philosopher and animal rights activist, suggests a thought experiment. Imagine a dedicated vegan responsible for the care of ten young children. It so happens that famine strikes and the children are all in danger of starvation except that our vegan carer owns a cow. Would it be morally acceptable for the vegan to stick by her principles and refuse to slaughter the cow to save the children? If the answer is no, then there seems to be some problem with the speciesist position. It would probably not be considered acceptable to slaughter one of the children to feed the others, after all. So, our intuition is that there must be some foundation for our moral preference for a human over an animal, at least in some extreme conditions. Perhaps the intuition is that there is moral value in feelings of kinship because this is a necessary feeling in order to be a fully healthy human, to flourish as a human being. If that is the case, then, kinship, for humans, is a kind of interest in the Singer sense and one that overrides other interests. That may be why we don’t find it reprehensible when a mother prefers the welfare of her child over that of another.

The moral value of ‘kinship’ overrides speciesism

If kinship carries moral weight, then the speciesist argument loses ground and a possible justification for preferring animals over human beings in research emerges.  Medical research is an attempt to save human lives and reduce human suffering (it has similar benefits for animal as well, of course, but we can set that aside for now, for the sake of simplicity). If, as scientists argue, this can only be achieved with the use of an animal model, then we are morally entitled to prefer the use of a non-human animal, so long as kinship has the moral value we are claiming for it and the suffering and distress of the animals is minimised as much as possible.

But what if this is all just a complicated exercise in justifying what we want to do anyway, what if our moral intuitions are just wrong? It is easy to imagine a Singerian arguing, in the case of our starving children and vegan nanny, that the cow has as much moral standing as any of the others: it has the same interest in living and not suffering the pain of hunger as the others and, what’s more, it may be better able to survive the famine given its ability to eat vegetation that cannot sustain humans. In that case, it seems the advocate of speciesism must argue that they all should starve together in the interests of admirable intellectual rigour, even if it feels a little hard on the children.

Using utility to resolve moral conflicts

As usual, though, the situation is more complicated. Peter Singer and his followers recognise that there is often a conflict of moral interests and so we need a framework for finding a resolution. This framework should not be  ad hoc or arbitrary or based on scripture or any other culturally specific text or tradition but should be rational. Within Singer’s argument the rational moral grounding is provided by utilitarianism the ethical doctrine first proposed by Jeremy Bentham in the 19th century. Utilitarianism argues that when two actions are in conflict, the morally correct one is the one that delivers the most happiness for the largest number (Bentham called this ‘utility’ for obscure reasons). In other words, the morality of an action is decided by its consequences, not by the intentions of the actor or anything else. Applied to the problem of our starving infants and their increasingly paranoid cow, a utilitarian might argue that killing the cow is justified despite it having a similar interest in living to the children because the slaughter would maximise future happiness (utility). If they all die, happiness would be at zero, and if a child was sacrificed to save the others, that would reduce overall happiness because of the distress of the survivors at their loss, the suffering endured by the child selected to die, and the indifference of the cow. 

How do you measure happiness?

Problems with utilitarian ways of thinking immediately suggest themselves: how can happiness be measured? How can the ‘happiness’ of a mouse, for example, be weighed against a person, or any other animal? Must we consider a well-intentioned action that has bad outcomes immoral instead of just unfortunate? The literature goes into all these problems and more at great depth, but for our purposes, it is at least clear that a utilitarian moral framework allows for the use of research animals in some circumstances. The human happiness delivered by a successful medical treatment can be great and long lasting while any pain or distress caused to the experimental animals is kept to a minimum and is of very limited duration. In the utilitarian scales, this tips firmly towards an ethical justification of animal research. It is a surprise to many people that Peter Singer, the father of the modern animal rights movement, comes to the same conclusion, although he argues for stricter controls and more work to reduce and mitigate the use of animals. Even without appealing to concepts such as kinship, in other words, the concept of speciesism, perhaps the most formidable intellectual weapon aimed against animal research by protest groups, does not carry the day. It is perfectly possible to allow the moral value of an animal’s interests and still justify its use in research – even if that research causes the animal harm or distress – so long as the future outcomes maximise happiness. 

Animal rights arguments

The only significant ethical argument against animal research that remains is based on the idea of rights. Just as humans have inalienable rights, the argument goes, so do animals. According to this view, the use of animals for research can never be justified for exactly the same reasons that we cannot justify using humans. But argument from rights has many more problems than argument from interests: from where are rights derived? What specific rights do animals have? Should rights be protected even when this is damaging to the welfare of the animal? This last point is perhaps the most salient. If we allow an animal has a right to its freedom, say, not to be kept in captivity (one of the key rights usually claimed by activists), then we are not only committed to ending all ownership of animals, but to the immediate release of all domestic animals into the wild even if that were to the detriment of the animals’ welfare as it surely would be. The problems mount at every step. How can it be possible to reconcile a vole’s right to life with a falcon’s right to eat? What possible mechanism could be constructed to resolve such conflicts and how much irreparable harm to natural ecosystems would follow if we built one? Without answers to questions like this it is hard to see animal rights arguments as much more than rhetoric.

Maximising future happiness and minimising present suffering is enough for an ethical justification of animal research

The case for ethical animal research, then, does not need as much building as it might at first appear. None of the major philosophical arguments for animal welfare exclude the possibility of ethical animal research. The harm that is done to animals in well-regulated research environments serves a higher moral purpose: the reduction of death and suffering by disease and other disorders. Of course, this is only true if pain, suffering and distress, are minimised – as they are through animal welfare regulations in the UK and EU for example. These regulations also require the application of the principles of the 3Rs – but it is quite obvious, all other things being equal, that the use of a mouse in an investigation into cancer development, for example, will create less suffering than using a person for the same purposes. 

So, a utilitarian calculation of maximising future happiness and minimising present suffering is enough for an ethical justification of animal research even for tough minded opponents of animal exploitation such as Professor Singer. But maybe justification is the wrong word. 

Are we not morally obliged to use animals in research?

If, as the biological sciences are almost unanimous in claiming, we cannot have new medicines without some animal research, and if there are hundreds of devastating human illnesses that will continue to cause misery, pain, and heartache without those new treatments, should we not think of animal research as a moral obligation instead? It is difficult science to do, both technically and emotionally, but if we choose not to carry it out, we are effectively choosing to allow human suffering to continue in the future that our efforts today have the potential to reduce or eliminate. We don’t know which suffering we will be successful in mitigating when, but we can be certain that progress is being made. Remove animal research and we don’t not remove suffering, we simply transfer it from the animals now (where it is carefully controlled and minimised, very often to nothing) to future humans. That is the heart of the ethical case for animal research and one that needs to be better addressed by those who oppose it.

Last edited: 7 April 2022 12:16

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• Published: 29 September 2004

Use of animals in experimental research: an ethical dilemma?

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Mankind has been using animals already for a long time for food, for transport and as companion. The use of animals in experimental research parallels the development of medicine, which had its roots in ancient Greece (Aristotle, Hippocrate). With the Cartesian philosophy in the 17th century, experiments on animals could be performed without great moral problems. The discovery of anaesthetics and Darwin's publication on the Origin of Species, defending the biological similarities between man and animal, contributed to the increase of animal experimentation. The increasing demand for high standard animal models together with a critical view on the use of animals led to the development of Laboratory Animal Science in the 1950s with Russell and Burch's three R's of Replacement, Reduction and Refinement as guiding principles, a field that can be defined as a multidisciplinary branch of science, contributing to the quality of animal experiments and to the welfare of laboratory animals. The increased interest in and concern about animal welfare issues led to legislative regulations in many countries and the establishment of animal ethics committees.

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Explainer: What Is Animal Testing?

Vaccines, medications and cosmetics rely on animal testing even though the process is cruel, unreliable and often inaccurate.

Explainer • Animal Testing • Policy

Words by Björn Ólafsson

The use of animals in experiments is so endemic that “guinea pig” is used as an alternative term for “test subject.” But underlying this ubiquity is a set of processes that harm animals unnecessarily: rats force-fed drugs designed to induce tumors, monkeys kept in tiny cages with chemicals irritating their skin and beagles euthanized without any anesthesia.

Critics say many of these experiments are unreliable and even unnecessary. Advocates for reduced animal testing earned a win in December 2022: the FDA announced that it would no longer require animal tests prior to approving a drug for human trials.

What Is Animal Testing?

Animal testing, sometimes called in vivo testing, is a process of determining if certain medications, vaccines and cosmetics are safe for humans by first experimenting with them on animals. Animal testing is common in most countries and has been used in some forms throughout much of human history.

Cosmetic Testing

Cosmetic testing is a process of using animals to test any cosmetic product before human use, such as makeups, lotions, creams, fragrances, oils or facial masks. 

Testing for Medicine

Medical testing involves using animals to examine new drugs, research biological systems, investigate genetic factors, delve into animal psychologies or test out surgical strategies. Nowadays, drugs are the most common form of medical testing on animals.  

The History of Animal Testing

Animal testing is a long-documented practice, with some of the oldest instances dating back to around 300 B.C. in ancient Greece. Yet while animal testing was widespread in the form of vivisection and practice for operations, it wasn’t until the 20th century that medicines were commonly tested on animals. In fact, several laws were passed in this period, including the 1938 Federal Food, Drug, and Cosmetic Act in the U.S., that encouraged or mandated the use of animals in testing before human consumption. 

What Types of Animals Are Used in Animal Testing?

Invertebrates.

Common invertebrates used in animal testing include fruit flies and nematode worms. Unfortunately for these animals, no federal protections exist to minimize their pain or suffering in the U.S.

Vertebrates

There’s truth in the common phrase “lab rat” — 95 percent of animals used in animal testing are mice or rats. Dogs, cats, pigs, monkeys, other primates, rabbits and sheep are all used in addition to rodents. 

How Many Animals Are Used in Experiments Each Year?

This is a difficult question to answer, because the U.S. Department of Agriculture only counts certain species of animals in its annual review of animal testing. Mice and rats specifically bred for testing purposes are not counted because they do not fall under the U.S. Animal Welfare Act.

However, it’s been estimated that at least 50 million animals are used in the U.S. every year. The real number is unknown and may be higher. Worldwide, exact numbers are unknown, but some estimate the number to be around 200 million experiments per year. 

What’s Wrong With Animal Testing?

Is animal testing painful.

Some researchers attempt to reduce the pain for animal test subjects, but many do not. According to the USDA animal usage summary report , roughly 8 percent of animals were experimented on with no measures taken to ensure pain reduction. This report does not take into account animals that do not fall under the Animal Welfare Act, so the real number is unknowable and likely much higher. 

Even animals protected by the Animal Welfare Act are often subjected to levels of pain that are hard to comprehend. Of all surgeries on animals, 40 percent do not report using anesthesia, and drugs are often force-fed to animals. Animals are also often killed after the experiments are completed, long before the end of their natural lifespan.  

Are Animal Testing Results Reliable?

Animal tests do not catch all possible side effects before drugs move to a later phase of testing. According to a 2004 report from the USDA, 92 percent of medicines that pass an animal testing phase will not proceed to market, and a major cause of this failure is safety problems that were not predicted by animal tests. More recent reports from scientists estimate an even higher number of 96 percent . 

There are a variety of reasons why animal tests are considered unreliable. According to a 2015 review in the Cambridge Quarterly of Healthcare Ethics , these include the effects of laboratory conditions; the different ways that diseases impact animals and humans; and the differences in physiology and genetics across species, all of which lead to inaccuracies. Due to such factors, a breakthrough meta-analysis published in Alternatives to Laboratory Animals in 2015 argued that a lack of toxicity of a drug in any of the five species most commonly used in animal testing — dogs, rats, mice, rabbits and monkeys — was not able to indicate the likelihood of a similar lack of toxicity in humans. In other words, animal tests don’t work. 

Advocates for animal testing often argue that the complexity of a living organism — the organs, circulatory system and genetic regulation — will affect drugs in a way that single tissue samples cannot. This argument fails to account for the fact that nonhuman systems are very different from human systems, which leads to inaccuracy. 

Animal testing can also lead to banning drugs that would benefit humans. For example, tamoxifen , a drug used to treat breast cancer, can cause tumors in rodents. If this drug had been tested on animals in early phases of research, it is likely the benefits of tamoxifen would have remained untapped. 

Is Animal Testing Cruel?

Due to the combination of low accuracy and high amounts of pain, it is difficult to argue that animal testing is not cruel. Animals such as rats, mice, dogs and chimpanzees are burned, poisoned, crippled, starved or abused in other ways via drugs, confinement or other invasive procedures.

Animals like these are sensitive to pain, emotionally empathetic and capable of forming social bonds. But to the researchers in charge of them, they are nothing more than tools. 

Is Animal Testing Archaic?

Due to the inaccuracy of animal testing, voices have arisen to criticize its outdated methodology. Not only is animal testing an old-fashioned practice that hasn’t been brought into the 21st century, but evidence shows it is likely holding back medical research. 

Is Animal Testing Wasteful?

Because of the inaccuracy of animal testing, many scientists and experts argue that its existence is inherently wasteful. British doctor Ian Roberts writes that “biased or imprecise results from animal experiments may result in clinical trials of biologically inert or even harmful substances, thus . . . wasting scarce research resources.”

Is Animal Testing Illegal?

Cosmetics testing has been banned in 42 countries and 10 U.S. states (California, Hawaii, Illinois, Maine, Maryland, Nevada, New Jersey, Louisiana, New York and Virginia). New York’s ban on cosmetic testing goes into effect in January 2023 , which makes it possible that more states will continue to follow their lead. 

No countries currently ban medical animal testing, but this may soon change. This year, Switzerland held a referendum on medical animal testing. A large Swiss pharmaceutical lobby campaigned against the initiative, which was ultimately unsuccessful. But the fact that animal testing went from untouchable fact to subject of a national debate sparks doubt about its continued acceptance in the future. 

Aren’t There Laws To Protect Animals Used in Experiments?

There do exist some laws to protect animals, such as the U.S. Animal Welfare Act. However, this law does very little to protect animals from pain, and doesn’t even count rats and mice as protected animals.

Cosmetic testing is far more controversial in the public sphere and therefore more heavily regulated. It is almost entirely banned in the European Union and other countries, including Guatemala, Colombia, India, Taiwan and the U.K. The U.S. has no federal cosmetics ban.

Why Are Animals Still Used in Experiments?

Despite the lack of sustained evidence for animal testing’s usefulness, and the possibility of cheaper alternatives (as discussed below), animal testing seems to be used far more often than it should be. Why?

First of all, the pharmaceutical industry has maintained a clear interest in preserving animal testing, and only very rarely review evidence about its actual usefulness. Another issue is scientific tradition and established practice. Scientists are likely to cite historical precedent as a reason for selecting an animal model, as opposed to the model’s similarity to human systems or effectiveness in predicting toxicity, according to a 2019 paper in Alternatives to Animal Experimentation . 

Should Animal Testing Be Banned?

Calls to ban animal testing because of its ineffectiveness and cruelty have been getting louder in recent years. Entire conferences are held to discuss alternatives to animal testing, and many petitions and campaigns are igniting across the world. These voices don’t just originate from the animal liberation movement, either. Prominent scientists , pharmaceutical bosses and concerned citizens are joining the chorus. 

Alternatives to Animal Testing

Thankfully, there exist several alternatives to animal testing, some of which have become more popular and common in recent years. 

In Vitro Testing

In vitro testing is a process of conducting an examination in a test tube using tissue samples.

Human Tissues

Real human tissue samples, which can be ethically donated to science as a result of surgeries or after death, are viable alternatives for testing localized drugs. For years, research has indicated that various in vitro methods can hypothetically outperform animal testing (and cost less too), although this form of testing is likely best used for understanding toxicity within a single organ or organ system, not the entire human body. 

A new human tissue testing method has emerged recently that shows promise. An in vitro skin testing model called h-CLAT recently entered use in Europe and Japan, paving the way for more techniques that don’t require animal experimentation. 

In Vitro Modeling Systems

Another form of in vitro testing involves a synthetic model that can replicate human systems. While less accurate, this method is cheaper and far easier to source, although it is best used for simpler human organs like the skin. One example, the EpiDerm technology , is already widespread for cosmetic purposes. This method is currently not used for large-scale medicinal approval, but instead to test if certain people are at risk for certain diseases. 

Computer Modeling 

Of all the alternatives, scientists are most excited about computer modeling techniques. Advanced computer modeling, sometimes called in silica testing, can create complex models of human body systems, even accounting for irregularities like prior diseases, as well as a vast array of genetic and demographic information. 

And they work better than animal models. A 2018 study found an accuracy rate of between 89 percent and 96 percent , while a 2017 study estimated the accuracy rate of one method of analysis at 96 percent : in both studies the computer models beat the animal testing experiments. 

Research Using Human Volunteers

Using human volunteers seems a bit dystopian, but science has progressed a long way since the unethical days of the 20th century. For starters, in some recent drug testing human volunteers only receive a microdose of the drug and are monitored in the presence of medical professionals to ensure safety. This microdosing method is promising, but still needs more research. Other forms of human volunteer research include the safe use of fMRI imaging, which has been shown to be very effective. 

Of course, ethics regarding human volunteers are critical. Scientists and researchers must take great caution not to compel participants into doing something unsafe and must mitigate risks as much as possible. Using human volunteers is also best done after one other method, like computer modeling, has been completed to mitigate risk. 

Animal Testing Facts and Statistics

• The majority of animals used in animal testing are exempt from the Animal Welfare Act because they are rats or mice.
• Rats have great memories and demonstrate empathy for other animals.
• Every year, the NIH spends nearly $20 billion on animal testing-based research.
• A majority of Americans disapprove of the continued use of animal testing.

What You Can Do

Consumers who want to avoid products tested on animals can look for a “vegan” or “cruelty-free” label when purchasing cosmetic products. They can also voice their support for policies to improve animal welfare in the medical industry like the FDA Modernization Act 2.0 , which passed the U.S. Senate earlier this year.

Independent Journalism Needs You

Björn Jóhann Ólafsson is a science writer and journalist who cares deeply about understanding the natural world and her inhabitants through stories and data. He reports on the environmental footprint of the meat industry, the alternative protein sector and cultural attitudes around food. His previous bylines include the EU Observer and Elemental. He lives in Spain with his two lovebirds.

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10 Psychological Experiments That Could Never Happen Today

Nowadays, the American Psychological Association has a Code of Conduct in place when it comes to ethics in psychological experiments. Experimenters must adhere to various rules pertaining to everything from confidentiality to consent to overall beneficence. Review boards are in place to enforce these ethics. But the standards were not always so strict, which is how some of the most famous studies in psychology came about. 

1. The Little Albert Experiment

At Johns Hopkins University in 1920, John B. Watson conducted a study of classical conditioning, a phenomenon that pairs a conditioned stimulus with an unconditioned stimulus until they produce the same result. This type of conditioning can create a response in a person or animal towards an object or sound that was previously neutral. Classical conditioning is commonly associated with Ivan Pavlov, who rang a bell every time he fed his dog until the mere sound of the bell caused his dog to salivate.

Watson tested classical conditioning on a 9-month-old baby he called Albert B. The young boy started the experiment loving animals, particularly a white rat. Watson started pairing the presence of the rat with the loud sound of a hammer hitting metal. Albert began to develop a fear of the white rat as well as most animals and furry objects. The experiment is considered particularly unethical today because Albert was never desensitized to the phobias that Watson produced in him. (The child died of an unrelated illness at age 6, so doctors were unable to determine if his phobias would have lasted into adulthood.)

2. Asch Conformity Experiments

Solomon Asch tested conformity at Swarthmore College in 1951 by putting a participant in a group of people whose task was to match line lengths. Each individual was expected to announce which of three lines was the closest in length to a reference line. But the participant was placed in a group of actors, who were all told to give the correct answer twice then switch to each saying the same incorrect answer. Asch wanted to see whether the participant would conform and start to give the wrong answer as well, knowing that he would otherwise be a single outlier.

Thirty-seven of the 50 participants agreed with the incorrect group despite physical evidence to the contrary. Asch used deception in his experiment without getting informed consent from his participants, so his study could not be replicated today.

3. The Bystander Effect

Some psychological experiments that were designed to test the bystander effect are considered unethical by today’s standards. In 1968, John Darley and Bibb Latané developed an interest in crime witnesses who did not take action. They were particularly intrigued by the murder of Kitty Genovese , a young woman whose murder was witnessed by many, but still not prevented.

The pair conducted a study at Columbia University in which they would give a participant a survey and leave him alone in a room to fill out the paper. Harmless smoke would start to seep into the room after a short amount of time. The study showed that the solo participant was much faster to report the smoke than participants who had the exact same experience, but were in a group.

The studies became progressively unethical by putting participants at risk of psychological harm. Darley and Latané played a recording of an actor pretending to have a seizure in the headphones of a person, who believed he or she was listening to an actual medical emergency that was taking place down the hall. Again, participants were much quicker to react when they thought they were the sole person who could hear the seizure.

4. The Milgram Experiment

Yale psychologist Stanley Milgram hoped to further understand how so many people came to participate in the cruel acts of the Holocaust. He theorized that people are generally inclined to obey authority figures, posing the question , “Could it be that Eichmann and his million accomplices in the Holocaust were just following orders? Could we call them all accomplices?” In 1961, he began to conduct experiments of obedience.

Participants were under the impression that they were part of a study of memory . Each trial had a pair divided into “teacher” and “learner,” but one person was an actor, so only one was a true participant. The drawing was rigged so that the participant always took the role of “teacher.” The two were moved into separate rooms and the “teacher” was given instructions. He or she pressed a button to shock the “learner” each time an incorrect answer was provided. These shocks would increase in voltage each time. Eventually, the actor would start to complain followed by more and more desperate screaming. Milgram learned that the majority of participants followed orders to continue delivering shocks despite the clear discomfort of the “learner.”

Had the shocks existed and been at the voltage they were labeled, the majority would have actually killed the “learner” in the next room. Having this fact revealed to the participant after the study concluded would be a clear example of psychological harm.

5. Harlow’s Monkey Experiments

In the 1950s, Harry Harlow of the University of Wisconsin tested infant dependency using rhesus monkeys in his experiments rather than human babies. The monkey was removed from its actual mother which was replaced with two “mothers,” one made of cloth and one made of wire. The cloth “mother” served no purpose other than its comforting feel whereas the wire “mother” fed the monkey through a bottle. The monkey spent the majority of his day next to the cloth “mother” and only around one hour a day next to the wire “mother,” despite the association between the wire model and food.

Harlow also used intimidation to prove that the monkey found the cloth “mother” to be superior. He would scare the infants and watch as the monkey ran towards the cloth model. Harlow also conducted experiments which isolated monkeys from other monkeys in order to show that those who did not learn to be part of the group at a young age were unable to assimilate and mate when they got older. Harlow’s experiments ceased in 1985 due to APA rules against the mistreatment of animals as well as humans . However, Department of Psychiatry Chair Ned H. Kalin, M.D. of the University of Wisconsin School of Medicine and Public Health has recently begun similar experiments that involve isolating infant monkeys and exposing them to frightening stimuli. He hopes to discover data on human anxiety, but is meeting with resistance from animal welfare organizations and the general public.

6. Learned Helplessness

The ethics of Martin Seligman’s experiments on learned helplessness would also be called into question today due to his mistreatment of animals. In 1965, Seligman and his team used dogs as subjects to test how one might perceive control. The group would place a dog on one side of a box that was divided in half by a low barrier. Then they would administer a shock, which was avoidable if the dog jumped over the barrier to the other half. Dogs quickly learned how to prevent themselves from being shocked.

Seligman’s group then harnessed a group of dogs and randomly administered shocks, which were completely unavoidable. The next day, these dogs were placed in the box with the barrier. Despite new circumstances that would have allowed them to escape the painful shocks, these dogs did not even try to jump over the barrier; they only cried and did not jump at all, demonstrating learned helplessness.

7. Robbers Cave Experiment

Muzafer Sherif conducted the Robbers Cave Experiment in the summer of 1954, testing group dynamics in the face of conflict. A group of preteen boys were brought to a summer camp, but they did not know that the counselors were actually psychological researchers. The boys were split into two groups, which were kept very separate. The groups only came into contact with each other when they were competing in sporting events or other activities.

The experimenters orchestrated increased tension between the two groups, particularly by keeping competitions close in points. Then, Sherif created problems, such as a water shortage, that would require both teams to unite and work together in order to achieve a goal. After a few of these, the groups became completely undivided and amicable.

Though the experiment seems simple and perhaps harmless, it would still be considered unethical today because Sherif used deception as the boys did not know they were participating in a psychological experiment. Sherif also did not have informed consent from participants.

8. The Monster Study

At the University of Iowa in 1939, Wendell Johnson and his team hoped to discover the cause of stuttering by attempting to turn orphans into stutterers. There were 22 young subjects, 12 of whom were non-stutterers. Half of the group experienced positive teaching whereas the other group dealt with negative reinforcement. The teachers continually told the latter group that they had stutters. No one in either group became stutterers at the end of the experiment, but those who received negative treatment did develop many of the self-esteem problems that stutterers often show. Perhaps Johnson’s interest in this phenomenon had to do with his own stutter as a child , but this study would never pass with a contemporary review board.

Johnson’s reputation as an unethical psychologist has not caused the University of Iowa to remove his name from its Speech and Hearing Clinic .

9. Blue Eyed versus Brown Eyed Students

Jane Elliott was not a psychologist, but she developed one of the most famously controversial exercises in 1968 by dividing students into a blue-eyed group and a brown-eyed group. Elliott was an elementary school teacher in Iowa, who was trying to give her students hands-on experience with discrimination the day after Martin Luther King Jr. was shot, but this exercise still has significance to psychology today. The famous exercise even transformed Elliott’s career into one centered around diversity training.

After dividing the class into groups, Elliott would cite phony scientific research claiming that one group was superior to the other. Throughout the day, the group would be treated as such. Elliott learned that it only took a day for the “superior” group to turn crueler and the “inferior” group to become more insecure. The blue eyed and brown eyed groups then switched so that all students endured the same prejudices.

Elliott’s exercise (which she repeated in 1969 and 1970) received plenty of public backlash, which is probably why it would not be replicated in a psychological experiment or classroom today. The main ethical concerns would be with deception and consent, though some of the original participants still regard the experiment as life-changing .

10. The Stanford Prison Experiment

In 1971, Philip Zimbardo of Stanford University conducted his famous prison experiment, which aimed to examine group behavior and the importance of roles. Zimbardo and his team picked a group of 24 male college students who were considered “healthy,” both physically and psychologically. The men had signed up to participate in a “ psychological study of prison life ,” which would pay them $15 per day. Half were randomly assigned to be prisoners and the other half were assigned to be prison guards. The experiment played out in the basement of the Stanford psychology department where Zimbardo’s team had created a makeshift prison. The experimenters went to great lengths to create a realistic experience for the prisoners, including fake arrests at the participants’ homes.

The prisoners were given a fairly standard introduction to prison life, which included being deloused and assigned an embarrassing uniform. The guards were given vague instructions that they should never be violent with the prisoners, but needed to stay in control. The first day passed without incident, but the prisoners rebelled on the second day by barricading themselves in their cells and ignoring the guards. This behavior shocked the guards and presumably led to the psychological abuse that followed. The guards started separating “good” and “bad” prisoners, and doled out punishments including push ups, solitary confinement, and public humiliation to rebellious prisoners.

Zimbardo explained , “In only a few days, our guards became sadistic and our prisoners became depressed and showed signs of extreme stress.” Two prisoners dropped out of the experiment; one eventually became a psychologist and a consultant for prisons . The experiment was originally supposed to last for two weeks, but it ended early when Zimbardo’s future wife, psychologist Christina Maslach, visited the experiment on the fifth day and told him , “I think it’s terrible what you’re doing to those boys.”

Despite the unethical experiment, Zimbardo is still a working psychologist today. He was even honored by the American Psychological Association with a Gold Medal Award for Life Achievement in the Science of Psychology in 2012 .

Watch CBS News

Harvard study on monkeys reignites ethical debate over animal testing

Updated on: November 21, 2022 / 12:54 PM EST / CBS/AFP

Mother monkeys permanently separated from their newborns sometimes find comfort in plush toys; this recent finding from Harvard experiments has set off intense controversy among scientists and reignited the ethical debate over animal testing.

The paper, "Triggers for mother love," was authored by neuroscientist Margaret Livingstone and appeared in the Proceedings of the National Academy of Sciences (PNAS) in September to little fanfare or media coverage.

But once news of the study began spreading on social media, it provoked a firestorm of criticism and eventually a letter to PNAS signed by over 250 scientists calling for a retraction.

Animal rights groups meanwhile recalled Livingstone's past work, which included temporarily suturing shut the eyelids of infant monkeys in order to study the impact on their cognition.

"We cannot ask monkeys for consent, but we can stop using, publishing, and in this case actively promoting cruel methods that knowingly cause extreme distress," wrote Catherine Hobaiter, a primatologist at the University of St. Andrews, who co-authored the retraction letter.

Hobaiter told AFP she was awaiting a response from the journal before further comment, but expected news soon.

Harvard and Livingstone, for their part, have strongly defended the research.

Livingstone's observations "can help scientists understand maternal bonding in humans and can inform comforting interventions to help women cope with loss in the immediate aftermath of suffering a miscarriage or experiencing a still birth," said Harvard Medical School in a statement .

The school added it was "deeply concerned about the personal attacks directed at scientists who conduct critically important research for the benefit of humanity."

Livingstone, in a separate statement , said: "I have joined the ranks of scientists targeted and demonized by opponents of animal research, who seek to abolish lifesaving research in all animals."

Such work routinely attracts the ire of groups such as People for the Ethical Treatment of Animals (PETA), which opposes all forms of animal testing.

In its statement, Harvard Medical School said PETA had published content regarding the study on its website that was "misleading and contains factual inaccuracies."

This controversy has notably provoked strong responses in the scientific community, particularly from animal behavior researchers and primatologists, said Alan McElligot of the City University of Hong Kong's Centre for Animal Health and a co-signer of the PNAS letter.

He told AFP that Livingstone appears to have replicated research performed by Harry Harlow, a notorious American psychologist, from the mid-20th century.

Harlow's experiments on maternal deprivation in rhesus macaques were considered groundbreaking, but may have also helped catalyze the early animal liberation movement.

"It just ignored all of the literature that we already have on attachment theory," added Holly Root-Gutteridge, an animal behavior scientist at the University of Lincoln in Britain.

McElligot and Root-Gutteridge argue the case was emblematic of a wider problem in animal research, in which questionable studies and papers continue to pass institutional reviews and are published in high impact journals.

McElligot pointed to a much-critiqued 2020 paper extolling the efficiency of foot snares to capture jaguars and cougars for scientific study in Brazil.

More recently, experiments on marmosets that included invasive surgeries have attracted controversy.

The University of Massachusetts Amherst team behind the work says studying the tiny monkeys, which have 10-year lifespans and experience cognitive decline in their old age, are essential to better understand Alzheimer's in people.

Opponents argue results rarely translate across species.

When it comes to testing drugs, there is evidence the tide is turning against animal trials.

In September, the Senate passed the bipartisan FDA Modernization Act, which would end a requirement that experimental medicines first be tested on animals before any human trials.

The vast majority of drugs that pass animal tests fail in human trials, while new technologies such as tissue cultures, mini organs and AI models are also reducing the need for live animals.

Opponents also say the vast sums of money that flow from government grants to universities and other institutes — $15 billion annually, according to watchdog group White Coat Waste — perpetuate a system in which animals are viewed as lab resources.

"The animal experimenters are the rainmaker within the institutions, because they're bringing in more money," said primatologist Lisa Engel-Jones, who worked as a lab researcher for three decades but now opposes the practice and is a science adviser for PETA.

"There's financial incentive to keep doing what you've been doing and just look for any way you can to get more papers published, because that means more funding and more job security," added Emily Trunnel, a neuroscientist who experimented on rodents and also now works for PETA.

Most scientists do not share PETA's absolutist stance, but instead say they adhere to the "three Rs" framework — refine, replace and reduce animal use.

On Livingstone's experiment, Root-Gutteridge said the underlying questions might have been studied on wild macaques who naturally lost their young, and urged neuroscientists to team up with animal behaviorists to find ways to minimize harm.

"Do I wish we lived in a world where generating this important knowledge were possible without the use of lab animals? Of course!" Livingstone said in her statement . "Alas, we are not there yet."

• Harvard Medical School

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The dark side of the animal experiments

Elif akkaya.

1 Uskudar American Academy, High School, Istanbul, Türkiye

Harun Reşit Güngör

2 Department of Orthopedics and Traumatology, Pamukkale University Faculty of Medicine, Denizli, Türkiye

The use of animals in research has increasingly continued, although there are serious concerns about appropriate methodology, moral issues and translation to clinical practice. The aim of the present article is to review the insufficiency of statements in ethical approvals to obtain animal welfare in real life practices and to draw attention to the need for an additional evidence-based audit system. In many countries, local Animal Ethics Committees are established to ensure that animals are treated in accordance with 3Rs (Replace, Reduce, Refine) principles. Although the ethical approval certificate which is taken before the start of research is considered as the proof of animal welfare, footages released from all over the world reveal the maltreatment. However, due to the scientific resource provided by animal models, it does not seem possible to expect animal experiments to be terminated in the near future. Addition of previously suggested welfare section to methods of study or including the ethical approval certificate does not seem to be sufficient practices to guarantee the animal welfare, since they are not based on audited evidence. The welfare certificate, in which the welfare is supervised by independent auditors, would serve as a proof of both the wellbeing of subjects and consequently the scientific reliability of data. Application of review and publication priority for the animal researches which have the welfare certificate in addition to the ethical approval would encourage the researchers to obtain this certificate. The achievement of worldwide consensus about content, requirements, and application methods of the welfare certificate should be in the scope of scientists in the near future to reach the more humane and more qualified animal experiments.

Many animals have similar body compartments and physiology as humans; therefore, they are used in scientific research and studies. The use of animals in medical research has a long history dating to the anatomical studies of Aristotle on various animals. Although there are serious concerns about the appropriate methodology and moral issues in animal studies and the transfer of data to humans, the use of animals in experiments has increasingly continued to the present day.[ 1 ] Currently, millions of animals are sacrificed worldwide annually, and many are suffering in harmful conditions for medical research involving the development of several medicines, vaccines, or surgical techniques.[ 2 - 4 ]

The 3Rs (Replace, Reduce, Refine) are recommended as fundamental principles for the use of animal model.[ 5 ] Replacement involves the alternative models to animal experiments such as in vitro methods or computer modelling. Reduction means to propose the minimum number of animals required to achieve the purpose of the research. Refinement consists of many different applications to minimize the suffering, distress, and the potential pain exposure throughout the research.[ 5 , 6 ] Guidelines for research ethics stipulate the principles to be applied throughout the scientific study from planning to publication and recommend a set of ethical standards including the welfare of animal subjects. Directive 2010/63/EU of the European Parliament and of the Council on the protection of animals used for scientific purposes designated that the measures should be taken for animal welfare and that animal testing is replaced, when there are possible alternative methods.[ 7 ]

All over the world in many countries, local Animal Ethics Committees are established to ensure that animals are treated in accordance with 3Rs principles.[ 5 ] In Türkiye, institutional local Animal Ethical Committees approve, revise or reject each application, whereas ethical committees in some countries have only consultant role.[ 5 , 8 ] Researchers are expected to perform all experimental applications in accordance with 3Rs principles and to take necessary measures for animals to prevent suffering, distress, and pain.[ 3 , 9 ] Whereas replacement and reduction principles can be controlled and modified by the supervision of ethical committee before the approval of the experimental study, among the 3Rs principles, refinement is the most ambiguous one and the least monitored rule.[ 5 ] Several authors have suggested adding an animal welfare section to the methods part of publications to ensure that the refinement rule of 3Rs principles has been properly applied.[ 10 , 11 ] Although the certificate of ethical committee approval which is taken before the start of research is considered as the proof of animal subjects’ welfare based on ethical and scientific standards, many footages released from many experienced animal research centers all over the world reveal the maltreatment and abuse of animals.[ 12 - 15 ] Addition of previously suggested welfare section to the methods part of the study or claiming that the refinement principle of the 3Rs is complied with in the ethics committee document does not seem to be sufficient practices to guarantee the welfare of animals, since they are not based on audited evidence. Therefore, although ethical guidelines and approvals are useful and required tools to establish the ethical limits of experiments on animals, there is a clear need for a new measure to achieve the welfare of animal subjects.

Examples of animal cruelty in the international media reveal the insufficient application of 3Rs in real life for a variety of reasons and the urge need for an evidence-based audit system throughout the research in addition to the ethical approval. First, some laboratories continue to neglect their animals or ignore the negative effects of certain practices on animals unrelated to the scientific purpose of the experiment as long as they achieve their goals. One of the largest primate research centers in the United States (US) - University of California, Davis (UC Davis) has also been the target of animal rights activists over several mistreatments of primates.[ 13 ] In 2005, the facility was fined, when seven monkeys died from exposure to extreme heat. Additionally in 2016, UC Davis was investigated about a primate which broke its legs, while escaping through an unsafe door and another primate which was injured in a similar incident. UC Davis has typically used dyes to identify individual primates; however, in 2018, a few weeks old seven baby monkeys died due to the toxic allergic reaction caused by the dye accidentally transferred from their mothers, although the baby monkeys were not the subjects of that experiment.[ 13 ] Both repeated similar incidences and addition of new different maltreatments by years from the same research center, even if it is a specialized center for these researches, suggest that ethical approval could not be the guarantee of animal subjects’ welfare.

Another reason why additional measure besides ethical approval is needed to ensure the well-being of animal subjects is that some staff abuses or makes fun of animals in the laboratory. To illustrate, in a footage published by Cruelty Free International from an animal experimentation laboratory in Spain, Vivotecnia, a male monkey was seen as pinned down on the table by a staff member who was collecting blood from its leg, while a senior staff member was seen as drawing a face on the monkey’s genitals. Vivotecnia is a Madrid-based research center conducting animal experiments for the biopharmaceutical, cosmetic, chemical, tobacco, and food industries from all over the world.[ 14 ] In such experienced experimental centers, laboratory workers after a while may begin to ignore that experimental animals are actually living beings and begin to think of them as tools that lead to a goal.

Finally, most of the animals in experiments may suffer from unnecessary pain and stress beyond the aim of experiment. Exposure of animals to this unnecessary stress affects not only the welfare of the animals, but also the scientific reliability of collected data. However, laboratory staff do not care that animals are exposed to this unnecessary stress as long as they can collect the data. A footage published by Cruelty Free International and Soko Tierschutz from a toxicology laboratory in Germany revealed the maltreatments of animal subjects for toxicology and dose ranging experiments. The Laboratory of Pharmacology and Toxicology carries out toxicity tests for agrochemical, pharmaceutical, and industrial companies worldwide. As evident in the footage from toxicology tests, although it did not serve for the purpose of the trial, it was ignored that the monkeys - fixed by their necks while waiting their turn - were exposed to watching the applications of experiment on other monkeys and experienced intense stress.[ 15 ] Although animal toxicity tests include the application of the dose causing serious harm to animal subjects, in an attempt to predict what a safe dose for humans may be, the results are not actual predictors of safety and effectivity in humans. Yet, the reactions to a particular substance for all species and humans might be quite different.[ 16 , 17 ] Moreover, collected data becomes unreliable due to the physiological changes in animal subjects caused by the severe stress exposure beyond the purpose of experiment.[ 18 ] Consequently, obtaining unreliable data due to unnecessary stress exposure of animals in addition to the scientific limitations of toxicology testing methods for predicting the safety of human use actually refers that many animals are wasted for nothing. However, if toxicology experiments are required, the endpoint should be clearly defined according to the purpose of the experiment and necessary measures should be taken to ensure both animal welfare and data reliability by preventing animal subjects from suffering pain, distress and abuse beyond the purpose of research.

In addition to these examples of abuse in animal experiments, a topic that has been discussed recently is that although thousands of animals are spent on scientific experiments, the majority of these studies are not published[ 3 , 19 - 23 ] or the impact of the published ones on scientific progress is controversial due to the limited transfer of animal experimental data to humans.[ 3 , 17 , 19 , 20 ] Öztürk and Ersan[ 3 ] reported that more than 40% of animal experiments that were represented at national orthopedic congress in Türkiye over a nine-year period were never published, and 38% of those that were published never cited or were cited only once. They found that 4,440 animals were euthanized for no obvious scientific gain in unpublished studies.[ 3 ] Unpublished animal studies result in waste of animal life.[ 3 , 19 - 23 ] Öztürk and Ersan[ 3 ] suggested that publishing even animal studies that did not find significant differences would be helpful to avoid duplication of the same study. There are guidelines such as the Animal Research: Reporting of In vivo Experiments (ARRIVE) guidelines to reduce the unnecessary animal experiments and to overcome the inadequate methodology in animal studies.[ 24 ] Researchers are expected to comply with the ARRIVE criteria and make the necessary effort to publish the results of animal studies and, therefore, the lives of animals sacrificed in experimental studies are not wasted for nothing.[ 3 , 19 , 20 ] van der Worp et al.[ 25 ] suggested that the only way to prevent the unreported data in animal studies was to have a central registry system for animal studies similarly to clinical trial registry systems.

Since animals are known to have similar ability to feel pain and enjoy life as humans, it would be morally unacceptable to treat animals only as ‘tools’ to advance the knowledge.[ 26 ] Ignoring the fact that animal subjects are also living beings during experiments may expose them to unnecessary suffering and stress beyond the scientific purpose of the experiment. However, due to the scientific resource provided by animal models, it does not seem possible to expect animal experiments to be terminated all over the world in the near future. Moreover, the US Food and Drug Administration (FDA) usually asks two or more animal tests before approval of human trials.[ 20 ] In this case, the recurrence of many negative examples that have been reported previously should be prevented by taking more strict measures in centers of animal experiments. Although requirement of ethics committee approval for publication acceptance is applied all over the world, ethics committee approval does not ensure the animal welfare and data reliability.[ 12 ] When an experimental study is carried out with the approval of the ethics committee, researchers are expected to comply with the 3Rs principles. Since the refinement principle is the most uncertain among these 3Rs principles and can be achieved by various methods and there is no consensus about it, the ethics committee approval of the study, unfortunately, cannot provide definitive proof of animal welfare.

In conclusion, since animals do not have the chance to defend their rights such as humans, there is a need for a supervisor mechanism independent of the researcher to supervise and report whether the welfare principle is actually met in experimental animal studies in the reallife practice. The welfare certificate, in which the welfare of the subjects is supervised during the experiment, would serve as a proof of both the well-being of the subjects and the consequently scientific reliability of the data.[ 27 ] In this context, the content of the welfare certificate includes the criteria that the researcher is routinely expected to comply with (humane endpoints, appropriate skills and training of researchers to minimize pain and distress experienced by animals, taking measures to reduce pain and distress, improved handling of animals, appropriate living conditions, etc.), but only the researcher's statement is not sufficient, and it should be also audited that the necessary conditions are met with the application of the evidence-based control mechanism. Audit of adherence to welfare certificate criteria could be checked with regular video records of applications and treatments which were sent to welfare audit organization, and additional spontaneous control visits applied by the welfare experts. Application of a review and publication priority for the animal experiments which have the welfare certificate in addition to the ethical approval certificate would encourage the researchers to achieve this welfare document. In this respect, editors and journals would have an important role and sanction power for the improvement of animal welfare in experiments.[ 28 ] The achievement of worldwide consensus about the content, the requirements, and the application methods of the welfare certificate should be in the scope of scientists in the near future to reach the more humane and more qualified animal experiments.

Conflict of Interest: The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Author Contributions: Devised the project, the main conceptual ideas and proof outline: E.E.; Interpreted the data, revised critically for the intellectual content: H.R.G.; Both authors approved the final version to be published.

Financial Disclosure: The authors received no financial support for the research and/or authorship of this article.