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Dissecting Values in the Classroom

Should animals be used for teaching in schools and universities, and if so, how? In many cases, alternatives might be just as good

by Jane Smith

Earthworms are not everybody's favourite creatures, so a teacher friend of mine was pleasantly surprised recently to find his lesson on earthworm physiology to a group of 15-year-old boys developing into a lengthy discussion about whether worms feel pain, and whether it is right that they should be killed and dissected in school. Students seem increasingly worried by the use of animals in the classroom. Even biology undergraduates may balk at animal experiments or dissections, and it is not uncommon for individuals or occasionally even whole classes of undergraduates to refuse to participate in certain practicals.

In Britain, procedures likely to harm vertebrate animals cannot be performed in schools. But vertebrates can be kept in schools as pets or for behavioural or breeding experiments. Schoolchildren may also dissect parts of animals such as eyes, kidneys or hearts obtained from butchers or may sometimes dissect dead animals, such as fish or rats. At university, science undergraduates can perform potentially harmful experiments on living vertebrates only under Home Office licence.

A range of benefits has been claimed for the various uses of animals in education. Keeping living animals in schools, for example, may give pupils the opportunity to investigate feeding, growth and reproduction, and might also foster their 'social' education - raising issues concerned with sex, caring and death, for example. Animals in schools can also inspire creative work in the arts and may help students to develop a respect for animals. The new National Curriculum addresses some of these educational objectives, requiring that young schoolchildren should be encouraged to develop an understanding of 'how living things are looked after' and should 'be able to treat them with care and consideration'.

Dissection of dead animals in school and undergraduate biology classes can, it is claimed, help students to learn about the internal structures of animals: how the tissues and organs look and feel and how they are interrelated. Dissection, its supporters argue, also gives students a 'hands-on' appreciation of the complexity and intricacy of organisms, and can help students to develop practical, manipulative and surgical skills. At university, the use of living animals in more invasive procedures might have further benefits. For example, such uses of animals might have great impact in the teaching of subjects such as neurophysiology, pharmacodynamics and animal behaviour. Through such work, it is argued, students can gain experience in the design and execution of biological experiments, can become skilled in the technical aspects of such experiments, and can develop an appreciation of the variability of biological systems.

For many people, whether or not animals should be used in education depends on the answers to two questions. First, could alternatives achieve some or all of the benefits sought from experiments or demonstrations on animals? And secondly, in the absence of alternatives, are the benefits themselves worth the suffering that might be caused to the animals used? The dilemma often seems particularly acute in education, where animals are used to demonstrate known facts, ideas or techniques, not to discover new knowledge.

In Britain, such considerations have already led to legislation that restricts the use of animals in education. Scientific procedures that cause 'adverse effects' such as pain and stress to living vertebrates are regulated by the 1986 Animals (Scientific Procedures) Act, and are allowed only at undergraduate level and above. The act specifically prohibits such procedures in primary and secondary schools. The restrictions extend to fetuses, including hen's eggs, from halfway through gestation or incubation, and larval forms such as tadpoles from the time they become capable of feeding independently.

Thus, in Britain, invasive uses of vertebrates in schools are prohibited in law. The educational benefits are believed to be too slight compared with the harm likely to be caused to the animals. This view is not universal. In schools in the US, for example, living vertebrates may be used in procedures likely to harm them. Recently concern has focused on the use of animals in research projects submitted to American high school science competitions - the school 'science fairs'. General anti-cruelty laws apply to animals used in this way, but there are no special restrictions in federal law. Several organisations in the US have issued guidelines on the use of animals, but these have no force in law and reveal considerable disagreement about what constitutes acceptable practice.

Present rules for the Westinghouse Science Talent Search competition, for example, prohibit projects involving experiments on live vertebrates, except observation of animals in their natural habitat. Guidelines issued by the National Association of Biology Teachers, however, exclude only experiments that would cause animals 'pain or distinct discomfort, or interfere with their health in any way'. They appear to permit experiments likely to cause stress or minor discomfort. At the other end of the spectrum, the rules for the International Science and Engineering Fair, which is open to school pupils aged between 14 and 17, permit experiments that cause vertebrates pain or distress, or otherwise harm them.

In Britain, under the terms of the 1986 act, living animals may not be used by surgeons or others to learn or perfect their techniques. The only exception to this rule is for practising microsurgery, and this may only be done by qualified microsurgeons. Medical and veterinary students learn surgery through apprenticeship, working under supervision on real human and animal patients. But in the US and some European countries, students may practise surgical techniques on rats and dogs. The animals involved are usually killed under anaesthesia, without being allowed to regain consciousness. However, in some institutions, including certain American and Dutch veterinary schools, animals are used in 'survival surgery': they are allowed to recover from the anaesthetic, and later subjected to further surgical procedures.

A group of veterinary students from Utrecht University in the Netherlands is campaigning to put a stop to survival surgery on piglets. They argue that survival surgery is not a necessary part of their veterinary training and say that they can learn practical skills in surgery using dead animals, clinical cases, or animals under 'terminal anaesthesia' that are killed after the operation, without being allowed to regain consciousness. Recovery of surgical cases can be studied in clinical practice. The objections being voiced by the Dutch students have been supported by lecturers at several universities, including several in Britain.

Despite the relatively strict controls on the use of animals in education in Britain, there are increasingly vociferous calls for further restriction - particularly for a complete ban on animal dissection, and on animal experiments in undergraduate courses (Box 1). Campaigning groups argue that the educational benefits claimed for animal experiments could be achieved in other ways.

Numerous potential alternatives do indeed exist. For instance, a catalogue published by the Universities Federation for Animal Welfare and the British Universities Film and Video Council lists more than 250 videos, films and computer programs that can replace animal experiments or dissections in science teaching - particularly in the fields of anatomy, pharmacology and physiology. In schools, slides, films, videos, computer programs, preserved animals and material obtained from the abattoir or butcher may stand in for whole animals, especially in dissection.

In higher education, computer programs have the potential to replace some invasive uses of living animals (Box 2). Particularly promising is the development of interactive video, in which interactive computer programs are enhanced with video pictures.

Some doubt whether the alternatives can bring the same educational benefits as the use of animals. Yet surprisingly few systematic comparisons have been made. A study reported in Trends in Pharmacological Sciences in 1987, under the headline 'Video teaching - glamour without effect', concluded that videotaped demonstrations were not effective replacements for demonstrations involving live animals. But the study compared video demonstrations of 'rabbit isolated heart preparation' and 'convulsions after intoxication with local anaesthetics in rabbits' with live animal demonstrations of 'rabbit anaesthesia' and 'rat paw oedema' - hardly a valid comparison. There is a pressing need for proper studies of the educational merits of animal experiments and their alternatives.

If animal experiments do offer educational benefits that cannot be achieved in other ways, are they worth the harm caused to animals? This question was one of those debated by the multidisciplinary working party convened by the Institute of Medical Ethics (IME) in 1987. Members of the working party agreed that some use of animals in biomedical research is necessary, but they could not reach a consensus on the use of animals in education.

Some members of the working party took the view that there should be no dissection of whole animals in schools, and that invasive uses of living animals in higher education were unjustified. Others argued that these uses of animals could sometimes be justified by worthwhile benefits that could not be achieved by the existing alternatives, and so ought to be allowed. Defenders of dissection emphasise the excitement and interest which it can generate among pupils. Properly organised and supervised, dissection can be one of the most memorable and instructive parts of a school biology course. But the critics point out that the opposite is also true: some pupils, as well as teachers, may object to the killing of animals for dissection, and some may be upset by it, and so perhaps be put off biology. The IME working party recommended that pupils who object to dissection should be allowed to study suitable alternatives, without prejudice to their marks or prospects.

This tolerant stance has now become official policy in Britain. The A-level examination boards have ruled that dissection should no longer be compulsory in practical examinations, and although dissection is sometimes suggested as coursework, the boards allow pupils who object to study alternatives.

In the US, a school student's 'right' not to dissect has been affirmed in the courts. Jennifer Graham, a 15-year-old Californian, refused on moral grounds to dissect a frog and, in consequence, was awarded low marks in class. She took the matter to court, where it was ruled that she should be allowed to dissect a frog that had died of natural causes. Although impractical, this solution upheld Jennifer's moral objection to the killing of a frog specially for dissection. More significantly, the case led eventually to the passage of a state law upholding the right of students under the age of 18 to refuse to participate in 'harmful' or 'destructive' uses of animals in education. Yet schoolchildren in the US continue to do invasive experiments on living vertebrates, and the IME working party urged the abolition of this practice. Barbara Orlans, a physiologist now working at the Kennedy Institute of Ethics in Washington DC, has been campaigning for many years on this issue. She argues that science fair projects in which vertebrate animals are harmed 'should be forbidden nationwide'.

The IME working party was also divided on whether the invasive use of animals is justified in undergraduate education. But they agreed that if such work is to be carried out, it should be carefully controlled in terms both of the numbers of animals used and the harm caused to them. In Britain, animals used in such work must normally be anaesthetised, and eventually killed without being allowed to recover consciousness so as to avoid postoperative suffering. The working party could not envisage an instance where surgery with recovery could be justified to fulfil an educational objective. For this reason, members were concerned to learn of the practice of survival surgery in some medical and veterinary schools in the US and Europe, and they urged that the practice be stopped.

In all of this, the working party noted, the manner and context in which the animals are used is of overriding importance. If animals are to be used at all, it is essential that students see them being treated in a sensitive and humane manner, and to good purpose. Finally, at school and university, balanced discussion of the moral issues surrounding the various human uses of animals should be part of the biology curriculum.

Controversy has surrounded the use of animals in education for more than a century. In August 1874, a protest against the use of dogs in an experimental demonstration created an uproar at a meeting of the British Medical Association, in Norwich. This appears to have been one of the events leading to the passage of Britain's 1876 Cruelty to Animals Act, the world's first legislation designed specifically to protect laboratory animals. At the meeting, there were vociferous protests against experiments performed by the French physiologist Eugene Magnan designed to induce epilepsy in two dogs. At one stage, the president of the Royal College of Surgeons of Ireland cut the bindings holding one of the dogs and released it. The RSPCA later took Magnan and the three Norwich doctors who had arranged the demonstration to court, accusing them of unnecessary cruelty to the animals. The Norwich men were found not guilty because they did not perform the demonstration, and Magnan had returned to France. Nevertheless, the magistrates granted that the RSPCA was justified in bringing the action, and declined to award defence costs.

Another famous case developed after two medical students attended a physiology lecture at University College London in 1903. They claimed that, in a demonstration by the lecturer, they saw a 'brown dog of the terrier type' inadequately anaesthetised and struggling in agony. Their claims were later held to be libellous, and the lecturer was awarded damages. Nevertheless, the 'brown dog affair', as it came to be known, was commemorated by a statue of a mongrel dog in Battersea Gardens. The statute was removed by Battersea council in 1910, but the memory of the incident lived on and a replacement statue was erected in 1985.

Although such protests are not new, the scale and organisation of opposition to the use of animals in education has been increasing. In Britain, over the past five years, the National Anti-Vivisection Society (NAVS) has orchestrated campaigns aimed at school and higher education students. The society is urging students to adopt charters, promoting 'violence-free science'. A host of student unions have signed a charter which states, among other things, that 'as a student I will be free to follow my conscience in refusing to perform violent practices in experimentation'.

The 'youth wing' of the NAVS, Animals' Defenders, publishes a range of posters and leaflets in which the AD rabbit, dressed in baggy T-shirt and dark glasses, urges school pupils to campaign on animal issues, including hunting, intensive farming, animal experiments and unwanted pets. On the issue of dissection, school students are asked to sign a charter which states: 'I do not believe it is necessary to take life to achieve exam results; I do not want to take part in, or to observe, dissection; I believe that my objections to the practice of dissection should be respected and that I should not be penalised by loss of marks if I refuse to participate in dissection; nonanimal alternatives to dissection should be made available to all students at the beginning of school courses.'

In the present academic year, another British animal rights organisation, Animal Aid, has launched a 'campaign for ethical science' in universities and polytechnics. It aims to 'raise healthy debate within science departments by informing first-year undergraduates of the case against animal experiments and their right to refuse to carry out animal practicals'. At the beginning of the autumn term last year Animal Aid mailed copies of its publication The Ethical Scientist to first-year science students at universities and polytechnics. The magazine contained profiles of students who had objected to the use of animals in their studies, and articles by opponents of animal experiments for research, outlining their views on the ethical position and on the use of alternatives.

Internationally, the more moderate European Network of Individuals and Campaigns for Humane Education (EURONICHE) links student groups in higher education throughout Europe including Denmark, Germany, Ireland, the Netherlands, Norway, Spain and Britain. The groups promote the use of alternatives and put pressure on educational and government authorities to offer students a choice over the use of animals. The organisation encourages a 'responsible, truly coordinated approach'; it does not call for a total ban on the use of animals and 'does not simply foster an atmosphere of protest'.

DISSECT A RAT OR TWO BY COMPUTER 

Computer simulations offer a practical response to the ethical concerns raised by the use of animals in education, and can also save time and money. Many such programs exist, though whether the simulations can provide all of the educational benefits claimed for the use of animals is still debatable. David Dewhurst and his colleagues at the Department of Applied Science at Leeds Polytechnic have recently developed numerous computer simulations of common laboratory practicals in physiology and pharmacology. These programs are used routinely at Leeds in teaching practical classes for undergraduates. The students can also rerun the simulations in their own time, so reviewing the experiments in a way not possible with animal-based practical classes.

The programs display the results of the simulated experiments on the computer screen as they would appear in the 'real' experiment: for example, students see the data as simulated pen chart, oscilloscope, electrocardiogram, millivoltmeter, spectro-photometer, or radioactive counter recordings. Using a program, students can, to a certain extent, control how the experiment is conducted, and are expected to collect data from the simulation in much the same way as they would in a real experiment. Most of the programs include an introductory section which outlines the experimental protocol; several allow teachers to add supporting text which students can call up and read during the simulation if they wish.

The programs use data derived either from animal experiments or from mathematical models. Data derived from mathematical models provides less realistic-looking results, but gives more opportunity for interaction by the students. In both cases, 'biological variability' is built into the results displayed on the screen.

One program developed by Dewhurst's team simulates the pharmacological actions of drugs on an isolated rabbit's heart. Students can investigate the effects of various drugs and ions on the heart, and can examine the effects of 'preloading' the heart, which, in the real experiment, would be done by inflating a 'balloon' inside it. Simulated responses - including heart rate, coronary blood flow and contractile force of the heart - are displayed in a form comparable to a trace from a chart recorder. The move now is towards the use of interactive video, in which video pictures are combined with computer simulations. This increases realism and allows students to interact with the image of the real animal, or part of it, on the video screen. Video does not do away altogether with the need for animal experiments; they must be performed at least once in order to obtain the pictures. But with video, just one or two animals can be used to provide educational material for an indefinite number of students, where otherwise a large number of animals would have had to be killed.

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