Every year, it is estimated that more than 115 million animals are used in laboratory research around the world. However, because only a tiny percentage of countries collect and publish data on animal testing and research, the specific number is unknown. In the United States, for example, up to 90% of laboratory animals (purpose-bred rats and mice (bred specifically to be used in experiments), fish, reptiles, amphibians, birds, and invertebrates) are omitted from official statistics, implying that official numbers published by the United States Department of Agriculture are undoubtedly an underestimation.

So, what is animal testing?

Animal testing refers to procedures performed on living animals for the goals of basic biology and disease research, evaluating the effectiveness of new therapeutic products, and testing the human health and/or environmental safety of consumer and industrial products such as pharmaceutical drugs, food additives, household cleaners, industrial/agro-chemicals, as well as cosmetics.

Experiments are frequently brutally painful for the animals involved and can last anywhere from a few days to several months or even years. All procedures, including those deemed to be “mild,” have the potential to inflict the animals pain and suffering on both a psychological and a physical level. Vomiting, irritation, diarrhoea, rashes, lack of appetite, bleeding, convulsions, weight loss, respiratory distress, paralysis, lethargy, salivation, bleeding, heart failure, organ abnormalities, liver illness, tumours, cancer, and death can all result from the experiment.

The amount of pain and suffering that can be inflicted on animals during studies is limitless. In some cases, animals are not given pain medicine to alleviate their suffering or distress during or after the experiment because it may interfere with the experiment. Animals are normally killed after an experiment to analyse their tissues and organs, while it is not uncommon for animals to be used in repeated studies over many years.

Common animal testing procedures

• Drug, chemical, or infectious disease exposure to levels that induce illness, agony and discomfort, or death.
• In toxicity testing, forced chemical exposure can include oral force-feeding, forced inhalation, injection into the belly, skin, muscle, and so on.
• Deprivation of food and water.
• Genetic modification, such as adding or “knocking out” one or more genes.
• Physical constraint for brief periods of observation or examination.
• Physical constraint over extended periods of time.
• Identification via ear notching and tail clipping.
• Recovery from surgical operations.
• Distressing behavioural trials, such as forced swimming or electric shock. 
• Causing burns, wounds, and other injuries in order to investigate healing.
• Other techniques have been used to construct “animal models” of human diseases ranging from cancer to stroke to depression.
• Infliction of pain for the purpose of studying its physiology and management.

History of animal testing

Animal testing has a lengthy history, with some of the earliest examples reaching back to roughly 300 B.C. in ancient Greece. Despite the fact that animal testing was ubiquitous in the form of vivisection and surgical practice, it wasn’t until the twentieth century that medicines were frequently tested on animals. Indeed, various laws were enacted during this time period, notably the 1938 Federal Food, Drug, and Cosmetic Act in the United States, which encouraged or required the use of animals in testing prior to human consumption.

What kinds of animals are used in animal testing?

Around the globe, many different species are exploited for animal testing. But the most frequent include rats, mice, rabbits, fish, hamsters, guinea pigs, cats, farm animals, dogs, birds, mini-pigs, and non-human primates (monkeys, and in some countries, even chimpanzees are used). Each year, more than 12 million animals are used in the European Union, with France, Germany, and the United Kingdom being the top three animal-using countries.

More than 3 million animals are used annually according to British statistics, however this figure excludes animals raised for study but put to death as “surplus” without being put through specific experimental procedures. Although these animals are nonetheless subjected to the hardships and deprivation of laboratory life, their deaths are not documented in official statistics. Complete transparency regarding animal use is essential, and that all animals raised, used, or killed for research purposes should be recorded in official data. Unfortunately, there are no reliable figures on how many animals are killed in laboratories each year.

How different animals are subjected to different experiments

• Dogs‘ hearts, lungs, and kidneys are purposely injured or removed in order to research how experimental chemicals may influence human organ function.
• To research how people could be impacted by the same condition, ferrets are purposely infected with extremely painful, potentially fatal infections (such as RSV, COVID-19, or Ebola) and not offered pain relief or therapy before death.
• Pigs are implanted with various gadgets (including pacemakers and dental implants) in order to research how human bodies could react to such technologies.
• Monkeys are separated from their mothers as infants in order to explore how intense stress affects human behaviour.
• Sheep are treated to high pressures (such as those found deep underwater) for hours at a time and then returned to normal pressure to examine their reactions.
• For the purpose of researching how nerve activity may impact human limb movement, cats with injured spinal cords are made to run on treadmills.
• To determine whether a chemical can cause cancer in humans, it is forced-fed to mice everyday for two years.
• Pregnant rabbits are force-fed harmful pesticides every day for several weeks to see how they could affect human mothers and babies if they were exposed to the chemicals.
• Endometriosis is induced in baboons via injection of endometrial tissue in order to research how the disorder affects humans.
• To research how humans might react to cigarette smoke, rats are placed in narrow tubes and forced to breathe cigarette smoke for hours at a time.
• In order to better understand how humans might be impacted by the same virus, horses are exposed to potentially lethal viruses (such hepatitis) and their symptoms are tracked.

What is wrong with animal testing?

Drug and chemical safety evaluations have been relied on laboratory research on rodents, rabbits, dogs, and other animals for nearly a century. In addition to the ethical problems they raise (inflicting physical pain as well as psychological discomfort and suffering on huge numbers of sentient beings), animal testings are time and resource costly, limited in the number of drugs that can be tested, offer little insight into how chemicals operate in the body, and frequently fail to accurately anticipate real-world human reactions. The utility of studies that “mimic” human diseases in the lab by inducing disease symptoms in other animal species is also being questioned more and more by health scientists.

Attempting to mimic human diseases or toxicity by inducing symptoms in mice, dogs, or primates has significant scientific restrictions that cannot be overcome. Symptoms and responses to prospective therapies reported in other species are frequently dissimilar to those seen in human patients. As a result, nine out of ten candidate medicines that appear safe and beneficial in animal investigations fail in human trials. Drug failures and research that never delivers due to inappropriate animal models not only stall medical progress, but also waste resources and endanger the health and safety of clinical trial volunteers.