Use of Non-Patient Animals in Veterinary Physiology and Pharmacology Courses

Gary Block

Introduction

Veterinary school physiology and pharmacology courses have traditionally utilized live animals in student laboratories and demonstrations. As attitudes toward animal welfare change and as alternatives become available, veterinary students and faculty have begun to reevaluate this practice. The education of future veterinary practitioners, researchers, and teachers would seem to be an ideal place to institute the "three R's" proposed by Russell and Burch's The Principles of Humane Experimental Techniques: reduction, refinement, and replacement.¹ Similarly, the NIH Guide for the Care and Use of Laboratory Animals dictates that alternatives to animal use in education and research be instituted whenever possible.² Many veterinary school physiology and pharmacology exercises may be candidates for reduction or replacement of animal use. An assessment of the use of animals in different veterinary schools can help identify areas where animal labs may not be necessary.

Methods

Responses to a 21-question survey on the use of non-patient animals in physiology and pharmacology classes were obtained from 52 students representing 20 of 27 American veterinary schools. Efforts were made to avoid selection bias by instructing those students who handed out the questionnaires to distribute them without regard for the recipient's views on animal exercises. The questionnaire only addressed the use of animals during the 1987-1988 academic year and does not take into account those schools that may be in the process of reevaluating or redesigning these courses.

Results

Use of Animals in Labs

Nineteen of 20 schools used live animals in physiology courses, 16 of 20 schools used live animals in pharmacology courses, and 15 of 20 schools used live animals in both courses. Approximately 2000 animals were used for the two courses at the 20 veterinary schools examined. Approximately 880 (44%) were killed in these labs.

The survey revealed marked variability of animal use in the study of specific topics. Virginia-Maryland College of Veterinary Medicine used over 350 animals during physiology and pharmacology courses, while University of California at Davis used only a single animal. At the University of Minnesota, there were 17 different physiology and pharmacology labs utilizing 211 animals, whereas only one cow was used in a non-terminal demonstration at the University of Pennsylvania. Respiratory physiology was studied at Ohio State in a terminal laboratory involving 15 dogs, while at many other schools, the same principles were conveyed using the students themselves in an obviously non-terminal exercise. Cardiovascular responses to sympathetic and parasympathetic drugs were studied at one school (University of Tennessee) using 17 goats in a terminal procedure; the same topic was addressed at other schools (University of Missouri, Tufts University) using a single animal in a demonstration format.

Certain subjects were studied with animals at only one school. For example, only Texas A&M used animals to demonstrate atrial and ventricular fibrillation, only Cornell studied the effects of thyroidectomy/thyroid hormone administration with animals, and only Tennessee used animal labs to illustrate pancreatic biliary secretion. Most of the more common physiology and pharmacology laboratory topics (hypovolemic shock, skeletal muscle activity, effects of autonomic drugs on blood pressure, etc.) were taught at one or more veterinary schools without any use of live animals.

Student Comments

Most students did not oppose all use of animals in demonstration labs, but there were several concerns, Twenty-six percent of the study's respondents answered that the labs "did not take into account the educational level of the student with regard to technical skills and general knowledge of the subject matter." Some students complained that the true aims of the lab were sometimes lost when they performed surgical and anesthetic procedures for which they were untrained. For example, first year veterinary students with little or no surgical skills performed thoracic surgery and tracheotomies at the University of Missouri and at Cornell University, respectively. A student at University of California Davis commented that she was taught how to do a bovine epidural nerve block prior to learning how to restrain a cow!

Some students complained that the emphasis in these exercises was more on lab write-ups rather than on the conceptual material. In particular, these students found that several exercises consisted of data collection only. Some recalled that certain physiology lab write-ups could have been completed prior to the lab if it were not for the need to obtain a few data points for a graph or chart.

Despite these concerns, many students found animal labs to be a welcomed relief from the seemingly endless succession of classroom lectures. However, 28% of respondents concluded that "the knowledge and/or skills obtained from these labs did not justify the use of these animals." In fact, several students believed that the labs had deleterious effects on students. For example, one student commented, "The lab content combined with the indifferent attitudes of many of my professors definitely had a callousing effect." Veterinary students representing 16 of the 20 schools agreed that "the stated objectives of the lab could have been satisfied in a way other than using live animals."

Discussion

The striking differences between veterinary schools in the number of different labs performed and the quantity of animals used demonstrates that many educators do not consider all of these labs to be "necessary." Andrew Rowan of Tufts University School of Veterinary Medicine wrote, "Too often educational exercises (which use animals) are instituted in a vague belief that this or that will be a 'good thing' but the actual educational objectives are rarely stated explicitly".³

Not only can unnecessary labs waste money and animals, they may also have damaging effects on students. Desensitization to animal suffering may be an untoward outcome of these exercises. Dr. Bernard Rollin, professor of physiology at the Colorado State School of Veterinary Medicine, noted:

I am often asked the same question by educators involved in (human and) veterinary medical education: 'Why do students come into school sensitive, concerned, idealistic, morally aware and suffused with a desire to promote health and alleviate illness and suffering, yet emerge four years later cynical, hardened, brutalized, and rigid, their ideals and enthusiasm forgotten?'⁴

J.A. Kelly suggested that, when students are exposed to unnecessary or aversive procedures, "...the emotional responses that can be aroused are antithetical to good observation. There is a blunting to perceptual accuracy that accompanies these exercises, making them even less instructive."⁵

Alternatives

Many lab exercises which currently use animals could easily be replaced with non-animal alternatives. In labs where the animal is utilized to confirm a known physiological principle via data analysis, a lecture or videotape on the subject combined with copies of the "data" for each student is one effective option. Another possibility is the case study approach, and many pharmaceutical companies provide such instructional materials. For those labs in which a live demonstration is felt to be essential, a professor could illustrate principles before the class with a minimal use of animals.

Veterinary schools are increasing their use of videotapes and movies in order to give students an accurate and consistently repeatable source of those facts and concepts which the instructor deems important.⁶ Instructors can produce videotapes themselves, or they may purchase video materials. An added benefit of audio-visual devices is that the student can observe medical and surgical techniques performed by skilled practitioners. This will avoid clumsy mistakes made by novice students, which may undermine the goals of the lab.

Also available are interactive videodisc programs, which can simulate experimental exercises realistically. The student can visualize the result of each decision, which helps dramatize events and aids memory. There are several such interactive programs, which can serve as reusable training devices. An interactive videodisc that simulates canine hemorrhagic shock is being used at Auburn University School of Veterinary Medicine.

Computer simulations also offer advantages which extend beyond decreasing the number of animals used. Many complicated biological events can be simplified and better demonstrated by computer. Some pharmacology programs demonstrate the actions of hundreds of drugs, a virtual impossibility when using animals due to time and financial constraints. The students can concentrate on specific concepts, further supporting lecture and textbook material. Simulators consistently yield rapid and reliable results. In the long run, the programs tend to be less expensive than the considerable costs associated with laboratory animal purchase, maintenance, and care.

Computer-linked mannequins provide the most sophisticated animal alternatives. Human medical schools have many such products designed to train their students, and recently this technology has extended to veterinary medical education. A canine cardiopulmonary resuscitation mannequin, Resusci-Dog, was developed at Cornell University School of Veterinary Medicine. Cardiac massage and resuscitation can be practiced and a femoral pulse can be taken on the “animal.” Resusci-Dog has the potential to replace approximately 100 dogs per year at Cornell alone.⁷ A similar mannequin exists for the study of glucose administration and insulin therapy. Like most rapidly evolving technology, the cost of production decreases substantially after initial design and construction. The first Resusci-Dog cost seven thousand dollars to produce while subsequent models cost only seven hundred.⁷ Nevertheless, most veterinary schools continue to use live animals to teach these topics.

Obstacles to Use of Alternatives

Some veterinary educators believe that students will suffer if they do not have experience with living tissue. Furthermore, some instructors are concerned that these alternatives will not reflect “biological variability,” which is an important concept. However, students have ample opportunity to gain “hands on” experience and to observe biological variability during their third and fourth year clinical rotations. In addition, physical exams, palpations, and other essentially non-invasive procedures can be utilized throughout the student's education as valuable tools to demonstrate variability.

There is anecdotal evidence that labs may be an “initiation” into the scientific community. For example, Dr. Rollin recounted a veterinary instructor who justified a particularly brutal first year experiment by saying that “it underscores to students that they are in vet school now”.⁴ The use of animal labs as a “rite of passage” is an ethically questionable practice.

Another obstacle to substituting audio-visual and computer alternatives in physiology and pharmacology courses is that those instructors who innovate new alternatives rarely receive academic recognition commensurate with their effort or originality. The Government Office of Technology Assessment (OTA) concluded:

In the long run, the most serious problem to developing these simulators may well be the lack of professional academic rewards for faculty members working in this area. Promotion, tenure, and salary increments are awarded predominantly for productivity in the research laboratory, not for efforts to develop innovative teaching techniques and materials. With essentially no external grant support for computer-based education activities and with few refereed high-quality journals in which to publish, two of the measures by which rewards are apportioned are not available to developers of novel educational software.⁷

Prospects for Change

The successful implementation of alternatives requires a concerned, committed faculty and administration. One way to assess the use of animals in labs is to establish a committee for annual reviews of the use of animals within each course. This will encourage professors to remove exercises from the curriculum when alternatives exist that may decrease animal use and also improve the quality of instruction. Student input can be a valuable asset in evaluating and revamping many of these laboratories. A 1987 survey conducted by the Committee on the Use of Live Animals in Teaching at Cornell University School of Veterinary Medicine revealed that 70% of the responding (veterinary) students felt that live animals should not be used in physiology laboratories.⁸ Subsequently, student input and the work of a few concerned professors resulted in a substantial decrease in the number of animals used in the course.

While student voices have initiated many of the changes involving nonpatient animal use in veterinary school, many students still appear to prefer to use live animals in laboratory exercises, even when alternatives are available. Just 56% of those students who believed “the stated objectives of the lab could be satisfied in a way other than using live animals” would have preferred to use non-animal alternatives. A stronger emphasis on ethics within the veterinary curriculum might increase student commitment to the reduction of animal suffering and the enhancement of animal health.

As instructors of veterinary medicine, faculty members have an implicit obligation to discuss the ethical issues which may arise directly or indirectly from a particular exercise. However, only 50% of student respondents recalled any mention by professors or other faculty of the ethical ramifications of these labs. A 1978 report of a British Association Study Group noted:

Ethics is not a word which is often used in association with the teaching of science. Indeed, a scientific training contains within it an attempt to convince the student that the practice of science can be aloof from value judgments altogether. The unfortunate consequence of this approach is that scientists tend to give insufficient weight to ethical issues. If the primary aim of education is the knowledge of values and the production of wise and adaptable human beings, then the discussion and teaching of ethics must form one of its cornerstones and not remain hidden away in the attic.⁹

Finding acceptable alternatives to the use of live animals in veterinary physiology and pharmacology courses is a complex challenge. The OTA noted:

Alternatives must satisfy the demands of science education, teaching both the scientific method and the fundamental skills and techniques necessary to carry out scientific investigation. Yet science education does more – as it trains aspiring students, it establishes a framework of values and molds attitudes that will long influence their work. Therefore, exposure to alternatives, particularly the concepts underlying animal use and alternative methods, strongly influences the paths investigators choose to follow in the future.⁷

Interestingly, British veterinary schools prohibit the use of non-patient animals in training veterinary students. The British Veterinary Association “finds the idea of making healthy animals sick for the purpose of training totally repugnant to the profession in this country.”⁷ Unlike Great Britain, the United States does not require postgraduate internships and/or residencies. Consequently, American veterinary students often need non-patient animals to learn many of the diagnostic and clinical skills. Indeed, a Cornell study revealed that 98% of students and 90% of the faculty believed that surgery with live animals should be an “integral part of the core curriculum rather than postponed to postgraduate education.”⁸ While adoption of the British system by American veterinary schools is unrealistic, the British approach to animal exercises provides a model for reducing the use of non-patient animals.

Conclusion

This study revealed wide variability in the use of animals within veterinary physiology and pharmacology courses. Many alternatives are available, and they are currently in use at many veterinary schools. The student survey also demonstrated concerns about the necessity of animal labs and the manner in which they are performed. Veterinary training that involves discomfort or death of animals can create a moral dilemma for veterinary students, many of whom pursue a veterinary education in order to help animals. These labs should strive to demonstrate certain clinically relevant facts, expand the student's powers of observation, and increase the student's understanding and awareness of the underlying mechanisms of physiological and pharmacological principles. Veterinary schools should seek alternatives which satisfy educational objectives, reduce animal suffering and loss of life, and which are more consistent with the prescribed responsibilities of the veterinarian.

References

1. Russell WMS, Burch RL: The Principles of Human Experimental Technique. London, Methuen, 1959.

2. U. S. Department of Health and Human Services, Public Health Service, National Institutes of Health: Guide for the Care and Use of Laboratory Animals, NIH Pub. No. 85-23. Bethesda, National Institutes of Health, 1985.

3. Rowan AN: Of Mice, Models & Men: A Critical Evaluation of Animal Research. Albany, SUNY Press, 1984.

4. Rollin BE: Animal Rights and Human Morality. Buffalo, Prometheus, 1981.

5. Kelly JA: Alternatives to aversive procedures with animals in the psychology teaching setting, in Fox MW, Mickley LR (eds): Advances in Animal Welfare Sciences. Washington D.C., Humane Society of the United States, 1985, pp165-185.

6. Physicians Committee for Responsible Medicine: Alternatives in Medical Education Non-Animal Methods. Washington, D.C., 1987.

7. United States Congress, Office of Technology Assessment: Alternatives to Animal Use in Research, Education, and Testing. Washington DC, U.S. Government Printing Office, 1986.

8. Sack W: The Use of Live Animals in Teaching. Ithaca, Cornell University Committee on the Use of Live Animals in Teaching. Unpublished as of November 1988.

9. Lockwood R: Ethical issues in the use of animals in higher education. Presented at Symposium for Animal Research and Animal Welfare: Northeastern Regional Meeting of the Animal Behavior Society. Albany, November 2, 1985.

Acknowledgement: This research was made possible by the Physicians Committee for Responsible Medicine summer fellowship program.

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