Medical Discoveries

• Testing on dogs led to the discovery of insulin in the early 20th century, which has saved the lives of millions of diabetics worldwide (1).

• Animal testing was used to develop the polio vaccine, which has reduced the disease to near-irrelevance (1). 

• The hepatitis B vaccine was developed using chimpanzees for testing (1).

• Advances in breast cancer, brain trauma, childhood leukemia, cystic fibrosis, malaria, multiple sclerosis, and tuberculosis are directly attributable to animal experimentation (1). 

• Animal research was instrumental in the development of pacemakers, cardiac valve substitutes, and anesthetics (3, 4, 5, 6). 

• Researchers Joseph and Charles Vacanti grew a human "ear" seeded from implanted cow cartilage cells on the back of a living mouse to explore the possibility of fabricating body parts for plastic and reconstructive surgery (40).

Humaneness

• According to the Humane Society International, animals are routinely force-fed, forced to inhale noxious compounds, deprived of food and water, physically restrained, and burned. Some animals even have their eyes clipped open, necks broken, and are decapitated (1, 7). 

• In 2010, the U.S. Department of Agriculture reported that almost 100,000 animals suffered pain during experiments (1, 7). 

• Animal research has been regulated by the federal Animal Welfare Act since 1966 including enclosure size, temperature, access to clean food and water standards for research animals, and regular veterinarian inspections (25).

• The Animal Welfare Act does not apply to rats, mice, fish, and birds, which account for 95% of the animals used in research (28). The animals covered by the Animal Welfare Act account for fewer than one million animals used in research facilities each year, leaving 25 million other animals without protection (29, 30, 31, 32, 33). 

• Violations of the Animal Welfare Act at the federally funded Lousiana  New Iberia Research Center in Louisiana led primates to severe psychological damage and engagement in self-mutilation (38). 

• All animal testing proposals must be approved by an Institutional Animal Care and Use Committee (26, 27).

Animal Similarities

• Chimpanzees and humans share 99 percent of their DNA, and mice and humans share 98 percent (1, 12). 

• A Mayo Clinic study revealed that 25 compounds that reduces the damage of ischemic strokes in cats and rodents had no beneficial effect whatsoever in people (1). 

• In the 1950s the sleeping pill, thalidomide, which was tested on animals prior to its commercial release, led 10,000 babies to be born with severe deformities (14). 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 (15, 16). 

• Animal tests on the arthritis drug Vioxx showed a protective effect on the hearts of mice. However, the drug caused over 27,000 human heart attacks and sudden cardiac deaths (17, 18). 

• According to cell biologist Robin Lovell-Badge, 94 percent of drugs that passed tests in animals failed in people (1). 

• Some chemicals, like Aspirin and intravenous vitamin C, are ineffective or harmful to animals are valuable when used by humans (22) (24). Fk-506 (tacrolimus), used to lower the risk of organ transplant rejection, was “almost shelved” because of animal test results (22). 

Alternatives

• Human genes cloned into microorganisms can yield more specific toxicology results than testing on animals (1). 

• COVID-19 demonstrated that researchers can skip animal testing and go straight to observing how vaccines work in humans (8). 

• College Medical Professor Nikolai Petrovsky and College Medical Dean Peter Hotez describe that testing vaccines on animals is essential to prevent “vaccine enhancement” where a vaccine makes the disease worse (9) (10) (11). 

• Vitro testing, tests done on human cells or tissue in a petri dish, can reduce animal testing (13). 

• 3D printing allows the possibility for tissue bio-printing. A French company is working to bio-print a liver that can test the toxicity of a drug (21). 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 (13, 19, 20) 

•  Studying cell cultures in a petri dish does not allow the study of interrelated processes occurring in the central nervous system, endocrine system, and immune system and conditions such as blindness and high blood pressure (12). Furthermore, evaluating a drug for side effects requires a circulatory system to carry the medicine to different organs (13). 

• Laboratory mice live for only two to three years, so researchers can study the effects of treatments or genetic manipulation over a whole lifespan and across several generations, which would be infeasible using human subjects (12, 34).

Additional Statistics

• About 26 million animals are used every year in the United States for scientific and commercial testing (2). 

• Humane Society International found that animal tests were more expensive than in vitro (testing performed outside of living organisms) in every scenario studied (40).

• A poll of 3,748 by the Pew Research Center found that 89 percent of scientists favored the use of animals in scientific research (37).

• A USDA January 2020 report found that in one year of research, California used more cats (1,682) for testing than any other state. Ohio used the most guinea pigs (35,206), and Massachusetts used the most dogs (6,771) and primates (11,795) (39).