The classical depiction of a scientific laboratory shows two eager scientists amidst a table of steaming beakers and flashing machines. Cages line the walls behind them, filled with mice or frogs. The scientist will grab one of these animals, inject him with some blue substance, and eureka! A new discovery has been made.
While this movie-like depiction may not be completely accurate, it touches on one absolute truth: animals do science’s dirty work. In all branches of biological research, animals are the test subjects for new drugs, new clinical techniques, and disease case studies. Year after year, millions of animals are subjected to life-threatening ailments that further our knowledge of the universe (Welfare Act Report). Current U.S. laws only require labs to report the use of dogs, cats, primates, and other large animals. Thus, officially, only about 1.4 million animals are reportedly used in labs each year. However, current estimates suggest that ninety percent of labs use other animals such as mice, rats, and birds that they are not required to report, bringing the total animals used each year to approximately 14 million. Of all the experiments that report their data, less than half are officially recorded as causing the animals pain, though this does not account for the other ninety percent of bird and rat labs.
There is no doubt that the laboratory environment is not suited for wild animals. It has neither the freedom of a natural habitat, nor the resources of a zoo. Instead, the animals receive only what science and politics dictate. In the United States, the Animal Welfare Act of 1966 is currently the only legislation regarding the scientific use of animals. The law requires that these animals are adequately fed and seen by a veterinarian at least twice per year. It also demands a hygienic experimental setting, but does not require that the animal “storage” areas be kept clean. Finally, the act contains several clauses preventing cruel treatment. The principle question is whether the numerous benefits of animal testing can outweigh the suffering endured. To answer such a question, one must consider the nature and degree of animal suffering and the ethical consequences of these actions in comparison with the positive outcomes of animal use in research.
Many experiments subject animals to physically painful processes in order to gather results. For instance, a study by N.L. Bodkin et al. utilized Rhesus macaques to explore the effects of gastric bypass surgery on weight loss. As many as 30 monkeys were anesthetized for this surgery and follow-ups included daily blood draws to check hormone levels. Monkeys that showed interesting results were “sacrificed” so that their brains could be examined. Though the laws are compassionate enough to require anesthesia to avoid excessive pain, these primates were still forced to undergo dangerous experimental surgery. The surgeries not only altered organ placement in the body, but also affected the hormone levels in the stomach and the intestines, resulting in appetite changes that could cause severe weight loss in animals whose natural diets differ from humans’. Additionally, some subjects did not survive the surgery or the recovery. These animals lost their lives in the name of modern science.
In other instances, lab animals are subject to physical harm even when no data is being gathered. Mice are common victims of these practices as they are used in a variety of experiments, specifically those that investigate transgenic properties. One such experiment required mice to breed in order to obtain an entire pedigree of genomes. In order to genotype each mouse, a sample of DNA is required. Because the epithelial cells in the tail are thin enough to dissolve quickly in solution, the DNA sample is typically acquired by docking the tail of each mouse, exposing the nucleus and DNA. Furthermore, as more and more mice are born and genotyped, researchers need a way to efficiently keep track of their subjects. However, since one mouse is generally indistinguishable from another, researchers often clip off a specific toe from each animal. That way, in any given cage, each mouse is unique. Mouse three would be missing its third toe, while mouse four is missing its fourth (Ku et al.). These techniques are handy shortcuts for lab technicians, but aside from the pain caused by the procedures themselves, docking often leads to excessive bleeding or infection (Saenger).
While there are laws that prohibit certain cruel procedures, they are currently not extensive enough to protect all laboratory animals. For example, the Animal Welfare Act of 2006 banned the docking of dogs’ tails and ears in the United Kingdom, but mice and other animals do not share that same protection. However, since mice, rats, and frogs are able to feel pain, just as dogs are, these laws should logically protect all domesticated animals in order to be morally consistent. Researchers can also find alternative ways of maintaining order in the cages. For instance, dying each mouse’s tail with different colored ink would cause minimum damage to the mice, while still making it easier to differentiate them from their cage-mates. Likewise, DNA can also be extracted from an animal without clipping its tail. A simple needle and syringe can provide a blood sample containing plenty of DNA. It may be more arduous to separate nucleic acid from blood serum than from epithelial cells, but that seems a small price to pay to avoid unnecessary pain in a living creature.
A Painful Debate:
Opponents of animal testing base their argument on the assumption that the animals do, in fact, feel physical pain. Without explicit data to defend this claim, such animal rights activists must rely only on the empathy of their audience. It is impossible to literally experience another’s pain, so researchers cannot conclusively determine whether animals experience the type of pain humans hope to avoid. Because animals have what has been called a “lower consciousness” and lack an ability to communicate with humans, there have always been questions as to whether animals truly feel or perceive pain in the same way humans can. In his book, Animal Liberation, Peter Singer demonstrates that there is sufficient evidence that animals can, indeed feel what humans would consider pain. For instance, certain behaviors such as writhing, facial contortions, yelping, and physically avoiding a learned source of pain have all been observed in mammals and birds.
In addition, these animals share a nervous system quite similar to that of a human, and each responds remarkably similar to sources of physical pain: dilated pupils, perspiration, increased pulse, and decreased blood pressure. Singer also explains that pain is most likely an evolutionary mechanism designed to help keep victims alive. The instinct to avoid painful experiences allows animals of all species to learn which behaviors and environments are safe and which are not. However, because humans no longer survive in the wilderness, our biological need for a pain- alarm system has decreased, while this need has increased for virtually every other species. Thus, it is highly likely that the ability to perceive and feel pain has been retained and honed throughout the years.
An interesting study performed in 2006 suggested that mice not only feel pain, but that they also empathize with other mice experiencing physical pain. Jeffery Mogil discovered that mice responded differently to pain when their cage-mates were present to witness certain procedures. Scientists injected acetic acid into the paws of two same-sex mice, causing them to writhe in pain. They found that mice who had shared a cage for at least two weeks tended to writhe much more violently when their cage-mates were in pain at the same time. Skeptical that the mice may simply be mimicking each other’s behavior, Mogil exposed one mouse to the acid while the other was exposed to heat. They reacted differently to the each source of pain, but in both cases, watching the other mouse seemed to exacerbate their own pain. The researchers then blocked the sense of smell, hearing, and pheromone production to test how the mice were communicating their panic to one another. They concluded that it is the sight of one of their own that induces this sense of empathy. This was surprising, as mice rely primarily on their sense of smell in day-to- day activities (Ganguli). The results of Mogil’s experiment imply that “low consciousness” animals are not given enough credit. “Lots of psychologists think top-down, hence equate empathy with complex cognition… which requires introspection,” notes researcher Frans De Waal, who took a keen interest in the experiment. The ability to feel empathy suggests that mice not only understand pain themselves, but are also capable of much greater cognitive ability than previously believed.
Even in cases in which the animals are not mutilated or killed, significant trauma can occur in the lab. For instance, in Harry Harlow’s famous experiment, baby rhesus monkeys were separated from their mothers at birth in order for scientists to study the psychological development of the infants. The animals were put in a cage with two surrogate mothers. One made of wire and the other made of terry cloth. Harlow et al. were able to watch the behavioral development of the foster monkeys and compare them to control rhesus, who were raised under normal conditions with regular exposure to their birth-mother. They discovered that the young monkeys had an astounding need for motherly comfort. Regardless of whether the wire-mother or the cloth-mother provided milk, they all preferred the company of the soft mother, with whom they could cuddle and feel safe. Because these monkeys lacked a true parental figure, they developed disturbing behaviors such as self-mutilation, unreasonable fear at the approach of living creatures (humans or fellow rhesus), and a disinterest in exploring new environments. Monkeys left in total isolation, without even a fake mother, became so emotionally distressed that they engaged in “autistic self-clutching and rocking,” and “emotional anorexia” as several monkeys died from refusing to eat.
Undoubtedly, Harlow did not know what to expect when he began his experiment, as psychology was not well understood at the time. As a matter of fact, this study, along with several of his other experiments, laid the foundation for much of today’s developmental psychology. In another study, Harlow designed what he dubbed, “The Pit of Despair,” in which infant rhesus lived in isolation in a dark chamber for up to a year after birth. Not surprisingly, the subjects rapidly became depressed and neurotic in a manner that has become the model for human depression. The trauma Harlow evoked in his test subjects was quickly evident and exceedingly cruel. Many of his subjects could not survive their emotional crises, and those who did were outcast from their social groups, forced to live the rest of their lives without any ability to learn, gather food, or find a mate.
There is no doubt that the laboratory life is not well suited for any animal. But if not for these nonhuman test subjects, humans would be without countless drugs and medicines that are taken for granted today. Specifically, the discovery of insulin, used by million of people on a regular basis, was the result of working with diabetic dogs (Karamitsos 1). Without this information, the mechanisms and physiology behind diabetes mellitus might still be a mystery. Thanks to Nicolae Paulescu, who is credited with first isolating insulin from a canine pancreas, this disease is treatable and is no longer drastically life-altering. Likewise, more modern treatments such as chemotherapy were designed based on animal models. Louis Goodman and Alfred Gilman, tasked with turning World War II chemical weapons into potential treatment options, induced lymphoma in mice using mustard gas in order to develop treatments (Origins of Chemotherapy). The result is a technique that revolutionized how cancer patients are treated to this day. Countless other examples enhance the list of animals’ contributions to science. Indeed, the list of biological accomplishments that did not involve animal subjects would be significantly shorter.
Even those who oppose animal testing based on principle must also consider the practical applications of specific animals in the laboratory. Since the human genome project was completed, there has been a growing interest in studying genetic diseases. In order to investigate the effects of gene-manipulation on an individual’s health, labs have dramatically increased their use of transgenic mice. A transgenic animal has had its genes manipulated, whether via gene silencing, induced mutations, or other ways of altering genetic information. Since the mouse genome has been completely sequenced, mice make up approximately 98% of all genetically altered lab animals, with the other 1% distributed among rats, pigs, fish, and amphibians (NC3Rs). While mice have been used in labs for centuries, this recent surge is no coincidence. First and foremost, they are mammals that share a great deal of their genes with humans and are thus ideal for studying human ailments. Furthermore, because they have been bred in labs for so long under controlled conditions, very little genetic variation occurs. Scientists can breed mice of any genotype because they can manipulate rates of recombination and gene frequencies. Finally, because mice are so commonly used, researchers have perfected drugs and tools specifically made to study them. Anesthetics, dissection tools, and even mouse-retina readers have been developed, making it a simple task for scientists to examine this creature in any way imaginable. If labs were to suddenly remove or replace mice with a different animal, it would take a significant amount of time and money to generate true-breeding animals and develop techniques and tools for a completely different species.
Some organizations encourage the increased use of mice on the basis that fewer animals of other species will be used. While this may be true in the realm of transgenics, there is another species that appears indispensable: primates. Primarily because humans are so closely related to them, primate subjects are the best available model of human behavior and physiology. In the aforementioned obesity study on rhesus macaques, monkeys were chosen because of how closely they mimic human behavior.
In the study the monkeys were given a high calorie, high fat diet with the freedom to eat whenever they chose. Like many obese Americans, the monkeys adopted a “couch-potato” life style. Not only was their anatomy similar, but like humans, the animals ate when they were bored or when they were not even hungry. Unlike humans, however, the monkeys could not lie or report false data about their calorie intake. Research teams carefully and individually observed the monkeys the entire time. In many ways, these monkeys are perfect experimental candidates since they are as close to human subjects as a lab could possibly ask.
The Trouble with Monkeys:
The 96-98% genetic similarity between humans and other apes is both a blessing and a curse (Chimps, Humans 1). While it has provided a perfect human substitute in experiments, as mentioned above in the obesity study, it has also sparked a great deal of controversy. Because these primates are so similar to humans, there is significantly more oversight and stricter laws limiting their use (Carbone 207). It seems that politicians have developed a system of determining the value of an animal’s life. The more closely an animal is related to the Homo sapien, the more unethical it becomes to expose them to laboratory experiences. Indeed, while primates are extremely difficult to gain permission to use, mice, who share about 90% of their DNA with humans, are widely used. Similarly, the use of fruit flies, which are another model organism in genetics, is not regulated at all since bugs are quite unrelated to humans. While there may be some logic to this spectrum approach, the ethical answers become hazy. On one end of the spectrum, it seems that a fly’s life is virtually worthless and requires no consideration. On the other end, a human’s life is far too valuable to compromise in experimentation. Or is it?
During World War II, as the Nazis corralled “lesser races” into ghettos, their scientists conducted a variety of experiments on human subjects. Jews, homosexuals, and Romanians were castrated without anesthesia to investigate possible forms of forced birth control. Others were dunked in freezing water to study hypothermia and to determine what temperatures were lethal. The lucky ones died. The less fortunate individuals lived to endure further experimentation. Without question this research was highly unethical and cannot be considered anything less than torture (Freedman). From this shameful chapter in human history, useful medical and physiological knowledge was acquired. Modern human testing would theoretically expedite the process of curing modern diseases, but when the cost of such knowledge compromises human safety and dignity, it simply is not worth it.
Perhaps nonhumans ought to be extended the same moral considerations. Aside from the aforementioned genetic link between humans, apes, and other mammals, nonhumans can suffer and feel pain too. In his Animal Research: A moral science, Bernard Rollin argues that animals ought not to be excluded from our moral parameters. The Nazis were wrong to use race and ethnicity to determine the value of an individual’s life. Rollin insists that “certain beliefs about animals—for example, that they lack a soul, are ‘inferior’ to humans in power or evolution, and lack reason or language—cannot morally justify their exclusion.” In other words, if humans are consistent with their moral outlook, our intellectual superiority does not justify abuse of “inferior” species any more than it allows for the discrimination against mentally handicapped individuals.
Rollin further argues that the use of nonhumans may actually be even more morally reprehensible. He points out that humans are able to understand when they are in pain. People have the ability to discern the source of distress and when it will end. They can reason that stepping on a sharp nail causes pain in their feet, and that after adding ointment and paying a visit to the doctor, their pain will be relieved. A sedated rat who is administered a new drug does not have these luxuries. It cannot understand why it suffers or identify the source. As a result, the rat cannot avoid suffering. It has no sense of when an excruciating experience will end. The rat is essentially consumed by the pain, and for that indefinite amount of time, knows nothing but pain (Kitchell and Guinan 1989). It is only fitting that humans take every precaution to prevent such suffering in any creature, human or nonhuman.
Advocates of animal testing argue that the use of animals in research is the natural course of history. When humans must choose between helping ourselves or helping animals, we should and will prioritize the well being of our own species (Khalifeh et al.). Thus, Khalifeh suggests that if we can cure cancer and save countless human lives, we should not hesitate to do so simply to protect frogs, mice, and rabbits. However, animal testing is not so black-and-white. There are several solutions that would allow scientists to continue their research without the need for nonhuman subjects.
Some animals suffer to provide the world with miracle drugs or new medical techniques. Yet far too many animals endure the hardships of the lab for trivial or failed experiments. Regulations limiting the type of experiment in which animals may be used would go a long way towards reducing animal testing. For instance, the obesity study involving rhesus macaques was simply not a useful experiment. One of the goals of the experiment was to develop a diet pill that would help fight obesity. The results were quite inconsistent. In one trial, the preliminary drug actually increased the appetites of the obese monkeys, causing them to double or triple their food intake. Ironically it is now being considered as a weight gain pill for cancer patients. Other trials were more successful, with up to 40% of the rhesus losing weight. Interestingly, the researchers did corroborate that calories, not fat, are primarily responsible for weight gain and obesity. While this is useful information, the study ultimately determined that a healthy diet and exercise are the best ways to fight obesity (Pollack 1-2). Aside from the fact that this experiment could have been easily accomplished using human volunteers, it also provided minimal useful information. After spending months of time, thousands of dollars, and the well being of dozens of monkeys, scientists merely confirmed what was already common knowledge. The lives and health of the rhesus macaques were jeopardized for nothing. True, there was initially potential to develop a new, truly potent diet drug to combat obesity, a prominent health issue. Yet there were plenty of diet drugs available already. Adding yet another pill to the stockpile of infomercial drugs hardly qualifies as a valuable research goal.
For legitimate medical experiments, protecting animals’ rights becomes trickier. In the United Kingdom, laws regarding animal testing revolve around the Three ‘R’s which allow labs to focus their efforts on reducing the number of animals used, refining experimental procedures so as to limit the demand for animals, and replacing animals with nonliving test subjects. Simon Festing and Robert Wilkinson discuss the work towards developing better in vitro technologies in their article, Talking point: Use of Animals in Scientific Research. In particular, British oncologists have begun using hollow-fiber systems to examine cancerous tumors. Researchers grow tumors in the hollow fibers, which are then injected into a mouse temporarily along with drugs, and are later removed for analysis. This technique introduces tumors to multiple organ system without permanently endangering or seriously hurting the mouse, and increases the amount of data extracted from a single animal (Double 2004). Likewise, cryogenic technology, which freezes cells at a temperature low enough to stall all metabolism, allows labs to store rodent embryos and cells of specific genotypes for a long period of time without the need to breed endless generations. While technologies such as these do not eliminate the need for animals, they certainly do decrease it.
In the United States, scientists are diligently working to develop machines that actually replace living creatures in experiments. Consider, for instance, the Tox21, a recently invented robot capable of testing potentially harmful chemicals entirely in vitro. The robot requires only minute tissue samples to assess the toxicity of chemicals, and can test up to 1,500 different tissues simultaneously. Not only can humans provide the small amounts of organ tissues without the need for animal tissue, but the robot can also determine how toxins will interact between different types of tissue. This crude imitation of the human body allows humans to accurately predict how the toxins will interact with our bodies in vivo (Jacobs 1). Unfortunately, the Tox21 will cost a lab about 10 million dollars – much more than many labs can afford to spend. However its overwhelming efficiency more than makes up for its price. It can acquire 2.2 million data points spanning thousands of different chemicals at any concentration within one week. It may take years and millions of dollars to assess the risks of even a single chemical using conventional animal testing techniques (Schmidt 117). As more of these technologies become available, the use of live organisms is becoming obsolete.
There is no doubt that animals have made major contributions to biological and medical research. But as we look to the future, the need for nonhuman contributors may be diminishing. Instead of using our intellectual gifts to force other animals to do our bidding, it can be focused on designing more technology that will continue to reduce our reliance on other species. Europe has made great strides to limit animal use in laboratories, and ultimately may reach the point where they will no longer use animals at all.
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