Ethical Issues in the Use of Animals in Biomedical Research

Richard R. Sharp, PhD
Center for Medical Ethics and Health Policy
Baylor College of Medicine

Historical Perspectives

The use of animals in biomedical research has a lengthy history. Early Greek writings (circa 500 B.C.), for example, describe the dissection of living animals by physician-scientists interested in physiological processes. These early vivisections appear to have been done mostly for exploratory purposes, however, to describe the inner workings of animals. Later, Roman physicians--including perhaps the single most influential figure in the emergence of the medical sciences, the physician Galen--began to perform what we would now regard as the first genuine experiments involving animals. Using vivisections to test specific hypotheses and explore competing explanations of biological phenomena, these early physician-researcher were among the first advocates of the idea that the use of animals in research was morally justifiable in light of the potential health benefits associated with those experiments.

Beginning with Galen, animal vivisection quickly emerged as an important tool for the study of anatomical structures and their functioning. Remarkably, Galenís teachings on human anatomy, which were widely used by physicians and scientists for nearly 1500 years, were derived from animal dissections and external examinations of the human body--he conducted no human autopsies. Later, as modern scientific principles were increasingly incorporated into the study of human physiology, physician-researchers such as Andrea Vesalius and William Harvey continued to employ animal vivisection in their investigations of the functioning of various anatomical structures, particularly the heart and lungs.

Throughout this historical period, few philosophical or moral objections were voiced regarding the use of animals in biomedical studies. This is perhaps surprising for two reasons. First, anesthetics were poorly understood and rarely used in animal vivisections. Second, the medical benefits of using animals in research were at best ambiguous during this period. Although both of these considerations would appear to argue strongly against the use of animals in research, there was clear moral consensus that the practice of animal vivisection was not unethical.

A Changing Moral Landscape

In the early and mid 19th century, this moral consensus becomes less clear. The availability of general anesthetics and the increasingly popularity of domestic pets (particularly in England), fueled anti-vivisection sentiments. By 1865, these reformist sentiments had become strong enough to prompt a response by the medical establishment. In his work, Introduction to the Study of Experimental Medicine, Claude Bernard was among the first to advance a moral argument in support of the use of animals in research. Arguing that the sacrifice of animals lives was essential to the advancement of medicine, and thus the relief of human suffering and extension of human life, Bernard argued that animal experimentation was ethically acceptable.

Changes in moral philosophy around that time, however, made Bernardís argument less compelling than it might have been were it introduced a generation earlier. In the early modern period, prevailing metaphysical beliefs about non-human animals included the Cartesian notion that animals were non-sentient automatons incapable of experiencing pain or pleasure. Only human beings were endowed with these special capacities, which they possessed in virtue of the fact that they had souls (which animals lacked). However, the emergence of utilitarianism as an influential moral paradigm called this perspective into question. Philosophers like Jeremy Bentham questioned whether animals truly lacked the capacity to experience pain or pleasure. In addition, Bentham argued that this capacity was a defining feature of membership in the moral community. For him, all pain and suffering was important in the assessment of the moral righteousness of an action, including pain and suffering that might be experienced by animals. If an action maximized good (pleasure) and minimized harm (pain), to the fullest extent possible, then that action was morally correct. If not, then the action was subject to moral disapproval.

As the Cartesian paradigm became more suspect and moral sentiments became increasingly more concerned with the minimization of pain and promotion of pleasure, including the minimization of animal suffering, defenders of animal experimentation were increasingly more subject to public scrutiny. In 1875, the Society for the Protection of Animals Liable to Vivisection emerged as an important force in the anti-vivisection movement. In the following year, the public reform campaign initiated by this organization was successful in establishing the first regulations governing the use of animals in biomedical research, the Cruelty to Animals Act of 1876. Although it did not prohibit all animal vivisection, this Act did require the use of anesthetics for many types of animal experimentation.

The passing of the Cruelty to Animals Act of 1876 was not altogether successful in answering the concerns of advocates on behalf of animal interests. Further support for the use of animals in research would come shortly thereafter, however, with advances in immunology and the study of infectious disease. The use of animals in the development of a vaccine for rabies and in the treatment of diphtheria provided compelling evidence of the health benefits associated with animal experimentation. These breakthrough accomplishments demonstrated in a manner that had not been possible before that time, that the use of animals in modern medical research could result in significant improvements in human health. Animal experimentation was now seen in a much less ambiguous way as a critically important tool in the war against human (and animal) disease.

Contemporary Themes

In the mid to late 20th century, other moral perspectives on the use of animals in research have emerged. Critics of animal experimentation, for example, increasingly stress the potential harms that might befall researchers involved in performing such studies. These critics maintain that moral sentiments can be deadened by persistent exposure to animal suffering. According to these critics, it is but a short step from feeling morally comfortable with the deliberate infliction of pain and suffering on a non-human animal to being morally comfortable with the infliction of pain and suffering on another human being.

Another argument that has emerged as increasingly more important to moral assessments of the use of animals in research begins with recognition of a sense of fraternity among all living things. It now appears that most animals have a variety of psychological experiences, including experiences that might be referred to as experiences of pain, pleasure, and other emotional states. If comparable human psychological states are important for the assessment of an actionís moral acceptability, then why is it the case that animal experiences should be treated differently?

These considerations have been used to suggest that dismissing these animal experiences as morally irrelevant, without providing a principled reason for such differential treatment, amounts to a form of "speciesism". Like racism or sexism, "speciesism" is intended to evoke the idea that it is morally indefensible to treat members of an entire category differently solely because they are members of that category. Rather, there must be some reason for treating those individuals differently. Thus, the challenge put forward by those critics of animal experimentation who appeal to speciesism is to provide substantive criteria for regarding animals as less-than-full-fledged members of the moral community. Lacking such substantive criteria, these critics claim that the use of animals in medical research is morally indefensible.

The appeal to speciesism is different from many of the arguments discussed above in an important way, namely, this new appeal is a rights-based argument. The claim is that animals possess cognitive faculties generally associated with membership in the moral community. Until it can be established that there are certain capacities that animals lack, and that other members of the moral community possess, animals should be treated as full-fledged members of that moral community--and with membership comes various moral rights.

This perspective stands in contrast to utilitarian-based appeals which may consider the experiences of animals in the assessment of the moral acceptability of animal experimentation. Although utilitarian perspectives frequently maintain that animal experiences are morally significant, and that animal pain and suffering should be factored into our moral assessments, utilitarians typically do not assert that animals have moral rights in the way envisioned by those who appeal to speciesism. Put in a slightly different way, anti-speciesists maintain that all animal experimentation is morally objectionable because it violates the inherent rights of the animal subject; in contrast, utilitarians maintain that some animal experimentation may be morally permissible because, on balance, the potential benefits of the research in question outweigh the potential harms to animal subjects (provided these harms have been minimized to the full extent possible).

Looking Ahead

Although moral debate regarding the use of animals in medical research continues to evolve, three main themes appear increasingly more prominent. First, the rise of radical animal-rights organizations like the Animal Liberation Front suggests that there is a small enclave of passionate individuals committed to the idea that all animal research is inherently unethical. How best to respond to those persons who are not persuaded by appeals to the potential health benefits of animal experimentation has been, and will remain, an important consideration for those research who advocate such practices.

Second, although detailed regulations governing the use of animals in research have been in place for several decades (see How to Work With Your Institutional Animal Care and Use Committee), many have expressed dissatisfaction regarding institutional commitments to upholding these regulations. The extent to which outside community representatives are adequately represented in institutional deliberations, for example, has been the subject of some controversy. Others question whether researchers pay enough attention to the justification of the increasing numbers of experimental animals required to conduct biomedical studies. As more federal and private funds are used to support medical research involving the use of animals, this concern will likely become more salient to the lay public (many of whom are unaware of the millions of animals sacrificed each year in animal experiments).

Finally, it is important to remind ourselves that several decades worth of experience with current regulations regarding the use of animals in biomedical research has produced a strong moral consensus for these practices. Researchers who fail to comply with those regulations should expect to be judged by their peers as unprofessional, to be subject to various institutional sanctions, and more generally, to face significant moral disapproval. Consequently, a third emergent theme in the evolution of moral discussions regarding animal experimentation will likely be the importance of increased regulatory vigilance and attention to matters of institutional compliance.

Study Questions

1. Sharp mentions the increasing popularity of domesticated pets as one factor in the emergence of anti-vivisectionist sentiments in England. Do you think biomedical research with cats and dogs should be held to higher ethical standards because these animals are kept as pets? Why or why not?

2. Suppose you are a member of an IACUC asked to review a study of the carcinogenic potential of a widely used pesticide. In their application the investigators estimate that approximately 1500 rodents will be required to produce definitive results. Several members of the committee express concerns about the high number of animals requested for the study. Apart from statistical considerations, what other factors should be used to determine the number of experimental animals that it is appropriate to use in biomedical research studies?

3. What types of people do you think should serve on IACUC's? Should an effort be made to include animal rights activists as members? What are some of the advantages and problems with this approach?

4. Many pet owners/keepers describe relationships with their pets in terms of "love", "friendship", "loyalty", and so forth. Do you think the ability to love or befriend another could be used to determine which types of animals can be used as (involuntary) subjects of biomedical research?

5. Suppose it is discovered that a graduate student is mistreating experimental mice by not euthanizing them in a timely manner (and allowing those animals to experience an unacceptably high level of pain). What would be appropriate punishment for this behavior? How about for a second or third offense? Would it matter if the offender was a university professor and not a graduate student? Why or why not?

© 2004, Richard R. Sharp