REGULATIONS AND LAW

Animal testing regulations are laws or guidelines that permit and control the use of non-human animals for scientific experimentation. They vary greatly around the world, but most governments aim to control the number of times individual animals may be used; the overall numbers used; and the degree of pain that may be inflicted without anesthetic.

Worldwide laws regarding testing cosmetics on animals

Procedures conducted on animals in the UK in 2017

Amount (%)	Procedure
43% (1.61 million)	Sub-Threshold
4% (0.14 million)	Non-Recovery
36% (1.35 million)	Mild
15% (0.55 million)	Moderate
4% (0.14 million)	Severe

INVERTEBRATES

Animal research employs much more invertebrates than vertebrates. Drosophila melanogaster, a fruit fly, and Caenorhabditis elegans, a nematode worm, are the most commonly used species. Since the innate immune systems of insects and mammals are identical, insects may be used to replace mammals in some studies. Some invertebrate systems are thought to be suitable substitutes for vertebrate systems.

VERTEBRATES

In the U.S., the numbers of rats and mice used is estimated to be from 11 million to between 20 and 100 million a year. Other rodents commonly used are guinea pigs, hamsters, and gerbils. Mice are the most commonly used vertebrate species because of their size, low cost, ease of handling, and fast reproduction rate. Mice are widely considered to be the best model of inherited human disease and share 95% of their genes with humans. With the advent of genetic engineering technology, genetically modified mice can be generated to order and can provide models for a range of human diseases. Rats are also widely used for physiology, toxicology and cancer research, but genetic manipulation is much harder in rats than in mice, which limits the use of these rodents in basic science.

PAIN AND EUTHANASIA

The idea that animals might not feel pain as human beings feel it traces back to the 17th-century French philosopher, René Descartes, who argued that animals do not experience pain and suffering because they lack consciousness. Bernard Rollin of Colorado State University, the principal author of two U.S. federal laws regulating pain relief for animals, writes that researchers remained unsure into the 1980s as to whether animals experience pain, and that veterinarians trained in the U.S. before 1989 were simply taught to ignore animal pain. In his interactions with scientists and other veterinarians, he was regularly asked to "prove" that animals are conscious, and to provide "scientifically acceptable" grounds for claiming that they feel pain. Carbone writes that the view that animals feel pain differently is now a minority view. Academic reviews of the topic are more equivocal, noting that although the argument that animals have at least simple conscious thoughts and feelings has strong support, some critics continue to question how reliably animal mental states can be determined. However, some canine experts are stating that, while intelligence does differ animal to animal, dogs have the intelligence of a two to two-and-a-half-year old. This does support the idea that dogs, at the very least, have some form of consciousness. The ability of invertebrates to experience pain and suffering is less clear, however, legislation in several countries (e.g. U.K., New Zealand, Norway) protects some invertebrate species if they are being used in animal testing


Worldwide laws regarding the formal recognition of nonhuman animal sentience and suffering

Regulations require that scientists use as few animals as possible, especially for terminal experiments. However, while policy makers consider suffering to be the central issue and see animal euthanasia as a way to reduce suffering, others, such as the RSPCA, argue that the lives of laboratory animals have intrinsic value. Regulations focus on whether particular methods cause pain and suffering, not whether their death is undesirable in itself. The animals are euthanized at the end of studies for sample collection or post-mortem examination; during studies if their pain or suffering falls into certain categories regarded as unacceptable, such as depression, infection that is unresponsive to treatment, or the failure of large animals to eat for five days or when they are unsuitable for breeding or unwanted for some other reason.