Here are some frequently asked questions (and their answers) about animals used in research that have been submitted by students.

1.    Why can't we use prisoners, criminals, rapists, and pedophiles (etc) for research instead of animals?

2.    Why are we still using animals for research when there are plenty of alternatives available?      

3.    Is there any limit to what is allowed to be tested on animals?

4.    Are some types of animals required to be given “play" time, like dogs?

5.    Are animals used in research tortured and put through unnecessary, painful experiments that lead to suffering?

6.    How do they choose which animals to test?

7.    Animal research doesn't work because animals and people are completely different.

8.    What would be the consequences if animal testing were reduced or eliminated?

9.    What happens to the animals when the test is over?

10.   Where do they obtain the animals?

11.   What is the worst test done on an animal?

12.   How many chimps die a year from research?

13.   What are some of the requirements needed to run an animal research facility?

14.   Are most chimps put down after being tested?

15.   Does any animal research result in the animals being returned to the wild?

16.   Are animals tested on repeatedly?

17.   What are the regulations about cage size?

18.   But what about all the side effects and recalls from drugs that have been tested on animals?


1.  Why can't  we use prisoners, criminals, rapists, and pedophiles (etc) for research instead of animals? There are several reasons why it is not appropriate to use inmates in lieu of animals for research. All laboratory animals are specifically bred for use in research. Those looking to research specific things can pick and choose the appropriate research model to best represent what they are studying and will give the most useful data. It also ensures that the data collected is consistent across the board due to the animals having no genetic variability when used in a study. Even though you and I are both human beings, my genetic background is still different from your genetic background. A Balb/c strain of mouse (your typical white lab mouse) will be more genetically similar to another Balb/c mouse than I would be to you.

Lab animals are purpose bred to be free of disease. I may have contracted malaria when I was younger when you didn't, making a sample of my blood a variable in the results. This would have to be accounted for or thrown out completely. You may have a mental disorder due to lack of neurotransmitters that has yet to make itself known and I may not. An animal bred for research comes with a clean bill of health and any and all anomalies are intentionally part of its genetic makeup or part of the study itself.

Another reason concerns the lifespan of the individual. The lifespan of a mouse, for instance, is significantly shorter than a person. This makes it possible to gather a sizeable amount of data over many generations within a short period of time. With people, you have a long lifespan and a very small sample size. The smaller your sample size, the less likely your results will be statistically significant making the whole endeavor invalid.

Lastly, there is an issue of ethics. Our justice system is not 100% perfect. This leads to ethical questions we must ask ourselves. What if someone was wrongfully accused of their crime? Who decides what person is to participate in a study, for how long, and who or what gives them the authority to make that decision? It also implies that prisoners are somehow of a lower status than animals. It implies that committing a crime removes their humanity and gives other law abiding individuals the right to do with them as they please. This doesn't sound much different than the argument against using animals for research, does it? Answered by Ashley W** -

Additional answer to question #1 provided by Understanding Animal Research. Click here to view the article.


2.  Why are we still using animals for research when there are plenty of alternatives available? As of yet, there is still no alternative research model or substitute for a complete biological system. If someone wants to research something affects a part or the entire lymphatic system of an organism, it would not be possible using the alternative methods available at this time. That being said, it is required by The Animal Welfare Law that any and all alternative methods must be used first before an animal model can be used for research of any kind. This law is part of what is known as the “3 R's" used in animal research, Replacement, Refinement, and Reduction. The previous is an example of Replacement where any and all alternatives must be used in lieu of animals. Furthermore, justification must be provided to any and all regulatory bodies for review before research can proceed with an animal model.

As improvements are made to alternative and in-vitro research methods, animal research models will be used less and less in the future. Research animals are very expensive from a purely practical standpoint and when it comes to research grant money, every penny counts. Currently, more and more studies are using alternative methods in conjunction with animal studies to supplement their research. Answered by Ashley W** -


3.  Is there any limit to what is allowed to be tested on animals?   Yes - projects that propose testing on animals MUST be scientifically justified and show a clear benefit for humans or other animals.  If non-animal alternatives are available, animals are not allowed to be used (i.e. a tissue culture can be used to determine the safety of chemicals so that it is deemed "safe" before use on animals and then people).


4.  Are some types of animals required to be given “play" time, like dogs?  Animals housed in research laboratories are provided with environmental enrichment.  Environmental enrichment is designed to allow the animals to perform species-specific behavior.   It includes special housing features (including things like resting boards, swings, and hutches) to objects like treats and toys. Dogs are given special consideration and are required by law to have daily exercise.  Non-human primates (nhps) are required by law to have environmental enrichment.  Enrichment for nhps can include, going to a "play cage;"  trying to get a special treat out of a puzzle feeder; or being offered other things like swings, toys, movies, radios, etc.  Most research institutions have environmental enrichment programs for all of their species:  mice and rats get nesting material or little hutches, rabbits and dogs get toys to chew on, cats and ferrets get little balls to play with, even the Xenopus, the African clawed frog, gets enrichment through items placed in the tank that can be used to hide.


5.  Are the animals used in research tortured and put through unnecessary, painful experiments that lead to suffering? The short answer is simply “No." Researchers are required by law to minimize any and all anticipated or observed discomfort of animals in labs. In fact, strict regulations and laws are in place to ensure this. Animal research is THE most heavily regulated activity involving the use of animals. In the United States, all procedures must be approved by a committee called IACUC, the Institutional Animal Care and Use Committee. IACUC ensures compliance and adherence to rules and regulations like those of the Animal Welfare Act and The Public Health Service Policy on the Humane Care and Use of Animals. They also review how every individual animal is going to be used for a study, paying close attention to any possible pain and stress involved in all procedures. Every effort is made not only by researchers, but by lab veterinarians and animal care staff, to ensure the animals are as happy as they can be. The majority of procedures involves no pain or discomfort at all and may only require visual observation (changes in behavior), a change in diet, or a single injection or blood sample. 

“Suffering" is a word that is not just limited to physical discomfort. It can also pertain to when an animal's social or environmental needs are not met. Fortunately for them, animal care staff and veterinarians are there to provide clean water, fresh food, and a clean, comfortable housing environment every day complete with environmental enrichment to stimulate their natural behaviors. For example, social animals like rodents are required to be housed in groups and are provided nesting material, toys, or houses so they can hide and feel safe in their environment.

Sometimes it is unavoidable for a study to take place without a procedure that will involve pain or discomfort. If this is the case, then justification must be submitted in writing and reviewed beforehand. Analgesia or anesthesia (depending) will be used to alleviate any discomfort during or after a procedure or surgery, and procedures are kept as short as possible. Blood is monitored for stress hormones as well as animals do not always display obvious signs of discomfort.

To put this into perspective, your pets at home and animals in the wild encounter more stress than animals are even allowed to have in a research setting by law. Further, it is in our best interest to make sure animals suffer as little as possible because a stressed animal is less likely to produce reliable results for research. Answered by Ashley W** -


6.  How do they choose which animals to test?   Each species offers a model for a particular area of study. For example, cardiovascular studies often use pigs because their anatomy and response to certain treatments are just like humans; flu studies use ferrets because ferrets get the flu just like people; hepatitis studies use woodchucks because they naturally develop hepatitis; but most studies (95%) use rodents, primarily mice, because of transgenic technology, mice have been bred to develop human diseases...these include, obesity, diabetes, cardiovascular disease, cancers, etc. 


7.  Animal research doesn't work because animals and people are completely different. Are we? We have the same organs. We have the same organ systems that work in the same manner and are controlled by the other same bodily systems. Our livers both interact with our blood streams and nervous system. Chemicals and compounds are received much the same way. Take vitamins for example. Guinea pigs cannot produce their own vitamin C and if it weren't for their research contributions, scientists would not have discovered how vitamin C works in a guinea pigs body and therefore, our own bodies.

The veterinary field contributes much to research for animals and people too! Different neurotransmitters and hormones work the same in their systems as they do ours. Many animal hormones have successfully been used in therapy such as oxytocin and vasopressin from pigs, insulin from cows or pigs, and calcitonin from salmon. Painkillers and antibiotics are another example of substances that work the same in our bodies as they do in animals. Any minor differences between us and animals are still useful and can point researchers into how different diseases work or how they may be treated. There is no such thing as “bad data" because it will always tell us something, one way or another. Answered by Ashley W** -


8.  What would be the consequences if animal testing were reduced or eliminated?  The consequences would be that medical and scientific advances would slow, then halt, and some say, even reverse.


9.  What happens to the animals when the test is over?  Most animals are humanely euthanized because in order to get all of the data needed to help advance medicine and science, tissues must be harvested and analyzed.  If this data is not needed (meaning everything needed was able to be obtained without harvesting tissues), the animals are sometimes adopted out. It is illegal to euthanize federally owned chimpanzees for research purposes. Only about .003%  of all animals used are chimpanzees, and out of this group they are "retired" to chimpanzee sanctuaries whenever possible.

10.  Where do they obtain the animals?  Most animals are bred specifically for research by licensed vendors.  A very tiny percentage of animals are obtained from "Class B dealers" who obtain animals and "condition them" so that they can be available for research.  These are rare and would only be used for things like aging studies, or studies that need animals that have parasitic infections for a long period of time or other diseases that cannot be induced in the laboratory.  To obtain quality research data - animals must be healthy and their health and genetic history must be known.

11.  What is the worst test done on an animal?  I would say - before it was known that animals feel pain (yes - it used to be that people didn't think animals could feel pain) and before Russel and Burch (in the 1950's) advocated the 3 R's, attention was not as focused on animal welfare as it is today - I would say that the work done with animals before 1950 was probably the worst ever done.  Since 1950 - the focus on good animal welfare = good animal science started to emerge. By 1985, when the Animal Welfare Act was amended, focus on minimizing pain and distress (and the requirement of the use of analgesics) became a major theme in the laboratory animal science industry. Today, pain is NOT allowed unless it is strongly, scientifically justified for the good of humans and animals. These studies make up less than 7% of work done with animals, and when pain is experienced, it is minimized as much as possible.

12.  How many chimps die a year from research?  Probably about 15-20 die per year due to old age or other clinical problems. It is illegal to euthanize federally owned chimpanzees for research purposes. Very few chimps are used compared to other animals.  More than 95% of the animals used are rodents and fish.  Less than .5% are cats and dogs.  Less than .1% of all animals used are nonhuman primates.  About .003%  of all animals used are chimpanzees, and out of this group they are "retired" to chimpanzee sanctuaries whenever possible.  Most are used for HIV and Hepatitis research - two very important human diseases that need to be studied.

13.  What are some of the requirements needed to run an animal research facility?

A ton!!  To start, animal care requires:

  • Proper cages (depending on the species this can be tens of thousands to hundreds of thousands of dollars)
  • Proper bedding (comfortable, clean/sterilized - depending on the species and research)
  • Proper food (nutrition, often sterilized)
  • Proper environmental enrichment
  • HVAC systems to ensure proper temperature, humidity, and that the air changes per hour
  • Pest control
  • Security
  • Daily access to veterinary care
  • Daily observation by trained professionals
  • Daily husbandry (food, water, clean cage, etc.)

Then, to use animals in research, you must have an IACUC (Institutional Animal Care and Use Committee) which at the very least includes a chair of the committee,  a veterinarian, and a member of the community not affiliated with the research institution. This committee is responsible for inspecting the animal research housing rooms and laboratories twice per year and reviewing the animal care and use program which includes:

  • Veterinary care for all the animals
  • Personnel qualifications and training
  • Facilities appropriate for the animals

IACUC's also have to read, review and approve (or not approve) EVERY proposal that will use animals. In other words, someone can't just walk off the street and say, I'd like to do research using animals - it must be scientifically justified and you must have all of the items (mentioned above) and many more in place.


14.  Are most chimps put down after being tested?  No - it is illegal to euthanize chimpanzees for research purposes due to the Chimpanzee Health Improvement, Maintenance, and Protection (CHIMP) Act passed in 2000. The CHIMP Act provides for retirement and lifetime care of chimpanzees not in active protocols, it prohibits breeding in federal retirement and it prohibits euthanasia for the convenience of a lab.


15.  Does any animal research result in the animals being returned to the wild?  Not in biomedical research; however, conservation efforts and other types of animal research may allow the animal to be released back into the wild. There are different kinds of research (not biomedical research) that use wild animals (for example: researching methods to have elephant tusks grow back; or other animal conservation-type research) - in this type of research, animals are probably released back into the wild.

16.  Are animals tested on repeatedly? Only if it is scientifically justified. In most cases, animals are only used for one research project.


17.  What are the regulations about cage size? The Animal Welfare Act Regulations and the PHS Policy (through a document called "The Guide for the Care and Use of Laboratory Animals") have detailed requirements for cage sizes of laboratory animals. At the very least, animals must be able to perform species-specific behavior and stand up, turn around, and rest comfortably. Most caging provided exceeds the minimal requirements.  Dogs are given special consideration as the law requires that they get a specific amount of exercise - which means they must have a large enclosure or be allowed to run around outside of their enclosure for a certain amount of time each day. Non-human primates are also given sufficient room for species-specific behavior.


18.  But what about all the side effects and recalls from drugs that have been tested on animals? If a drug is slated to go through a testing, it first must go through rigorous screening processes using alternative methods to animal research such as computer screening or test tube methods. The animal research part shows how the compound behaves in a living body and if any toxic effects are present before it is delivered to people volunteering in clinical trials.

If there are any issues that are not revealed during initial in-vivo results, they will frequently show up during the animal testing stage if any such problems are present. This is due simply to the nature and limits of the alternative methods themselves. For example, if a substance is given to an animal by mouth it could be modified during the digestion process, making that substance less effective or the opposite could happen the substance may increase in toxicity. These whole body system tests are critical because they will expose any undesirable effects and it can be pinpointed where and how it happened. Because of our bodily system similarities, this reveals to the researchers any undesirable effects that would happen to a person taking the compound as well. This is the whole point to catch any potential issues BEFORE they happen.

That being said, keep in mind that a new drug or therapy will be tested on approximately 15 times as many clinical trial volunteers as animals. Think about that for just a minute and think about what that means in terms of statistics and numbers. Clinical trials involve testing a potential drug candidate on anywhere from 3000-5,000 volunteers and human patients. If undesirable side effects show up during this stage of the game, then it is very difficult to have discovered it before this during in-vitro or in-vivo testing. Answered by Ashley W** -


**Ashley W has over 11 years of experience in the biomedical research industry. She earned her B.S. in Animal Science, and she currently works at NC State College of Veterinary Medicine. Ashley is a manager of a Gnotobiotic lab doing research in germ-free mice. She regularly contributes to science-focused social media outlets such as Facebook, Twitter, wiki forums, and as a guest contributor on blogs. Ashley's other interests include education and outreach for the lab animal sciences, researching and learning new topics outside of her comfort zone (currently anything quantum mechanics), stargazing, cooking, and general nerdery. Ashley can be contacted via email at PSBR thanks Ashley for her contributions to this FAQ page!

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