Most drugs, therapies, or experiments, will have gone through animal testing at one point or another. The ethics of this have been debated — but what are the practicalities? What are the lives, the origins, and the potentials, of laboratory animals?
There are two kinds of lab animals; Class A and Class B. Class B animals can come from almost anywhere. Backyard breeders, who breed less than a certain amount of animals per year, can sell their unsold animals to dealers or to testing facilities. Animal shelters are often also a source for Class B dealers, depending on where they are in the United States. Some states require their publicly funded shelters to sell animals to dealers who request them. Some states forbid it. Others vary their rules according to the circumstances. These dealers usually have to supply some medical papers proving that the animals don't have diseases that might spread to the rest of the lab, or have any kind of extreme medical conditions.
Class A animals are a different story. They are bred, and raised, to be lab animals. This means they have to satisfy a number of conditions so that the information gotten from them will be useful to humans. They can't have any of the accidental medical quirks that rule so many humans out of laboratory testing. They have to be the 'average' mouse, or fruit fly, or chimpanzee, without heart conditions, genetic anomalies, or particularly bad viruses. But while they can't have accidental quirks, many animals can have genetic or medical quirks bred into them. Labs have special needs, and if they need a bunch of lab mice who are designed to be obese, or to be diabetic, or bald, they can literally call a lab and have a bunch engineered for them.
Basic Lab Animals
The idea of animal experimentation is never savory. There's no way around the fact that animals undergoing experiments will be subject to medical procedures, experimental drugs, or have medical problems induced, and that they will most likely be killed and dissected after any procedure is over. However, there are both practical and legal reasons why lab animals are kept healthy. Sick, stressed, or injured animals would not be good subjects, particularly for companies or organizations trying to get their products approved.
The Animal Welfare Act covers most lab animals, and provides guidelines for pain alleviation during procedures, food, and housing. If anyone wants government money, they have to comply with the Public Health Service Policy regarding minimum housing conditions for animals. There are detailed guides that require labs to keep animals in areas that are not overcrowded, while still allowing them contact with other animals.
When breeding and raising lab animals, centers have to cover the health basics, keeping the animals free from serious disease, parasites, or infections. When bought or wild-caught animals are brought in, they go through quarantine before they're integrated into the general population. Labs also have to keep a close eye on which animals breed. Some animal lines are closely monitored to ensure genetic diversity, others are deliberately inbred, and still others are mutated or genetically adapted. Some inbred lines go back almost a century. Some animals, on the other hand, are entirely new.
Designer Lab Animals
The most commonly made custom animal is the traditional lab rat. These are made when genetic material is injected into mouse blastocytes, which are then implanted in female mice. When the mice give birth, the pups are checked to see if they carry the right genes, and then moved to a special population to breed. Breeding facilities have a selection of transgenic animals, and can even offer specially designed animals to experiment conductors.
One of the newest innovations is 'humanized' mice. This was still just a possibility a few years ago, but in 2009, German researchers announced that they successfully implanted human genes associated with language into the brains of mice, causing neurological differences. Ever since then, companies have been expanding the kinds of human genes that can be transferred into mice, allowing companies to study their effects, and drug effects on them, without the danger of testing on humans or the expense of testing on chimps.
Diabetes on demand is another mouse model. A certain gene is knocked out of the mouse, causing it to gain more weight and metabolize glucose badly. This, in turn, causes half the mouse population to develop diabetes when fed a high-fat diet. Scientists studying either treatment or prevention of diabetes can order up a population of these with the certainty that they will have a specific diabetic population of mice soon enough.
Scientists can use mice to be the first to test efficacy in depression medication by ordering mice that cannot properly manufacture serotonin. These tend to be both anxious and depressed. Other labs can order rats that have their nociceptin receptors made inactive, which makes them prone to drug addiction. Immuno-compromised rats are available. Rats with deficient livers or intestines are available. Rats with different colored neurons in their brains are available. And more standard animals are being created all the time.
Is the End of Ape Testing Near?
Chimpanzees, and other great apes, are the most controversial subjects of medical experimentation. The testing began in the 1920s, got a resurgence in the 1950s, with the space program, and again in the 1980s when it seemed like chimpanzees were promising test subjects for AIDS research. Now they are most used for hepatitis research, being the only animal model shown to be susceptible to all types of the disease. Research conducted on them yielded a hepatitis B vaccine, and they are now being used in the United States for research on hepatitis C.
In many ways, the closeness of chimps to humans makes them both the perfect model and the most excruciating one. They live for roughly-human lifespans, so many of them are experimented on from birth to death — about sixty years. They're highly social and highly intelligent, so they're more aware of their conditions than other animals.
Recently, the controversy has begun to heat up. The New Iberia Research Center has been accused of breeding federally-owned chimpanzees to maintain their stock, despite being banned from doing so. The National Center for Research Resources, which oversees chimps that are being tested on, declined to investigate this breach of the ban. More recently, the NCRR made plans to give chimps that they had confiscated from a lab that had been shown to practice animal cruelty, and that were publicly said to be 'retired,' to a new research facility. When the public protested, the NCRR publicly stated that they would wait for an investigation to see whether this move was ethical, while privately laying out a plan to move the chimps anyway.
Whether experimentation on chimps is immoral or critical to ending human suffering, one thing isn't in doubt: It's expensive. This could be the idea behind the title of the The Great Ape Protection and Cost Savings Act, which is sitting, waiting to get out of subcommittee in the House of Representatives. The act, or a version of it, has been introduced repeatedly, but never before with the word 'savings,' in the title. The bill has supporters, who say it's the cost-effective and correct thing to do, and detractors, who say that unchecked hepatitis is more costly and immoral. If the bill passes, chimp and bonobo testing, already banned in many European countries, may be a thing of the past in the United States.
But whatever happens with chimps, one thing's for sure: With the increase in biomedical research potential, overall animal testing will be here to stay.
Top Image: National Cancer Institute
Fat Mouse Image: Human Genome Wall
Chimp Image: Thomas Lersch
Via LabAnimal.com, Library Index, AWIC, ALAAS, APS, FCCC, and Wired.