Ethical concerns regarding the use of animals as a source of organs, cells or tissues for transplants

[Source: Council of Europe 2000: Working Party on Xenotransplantation, Strasbourg, July 2000.   Reprinted with permission.]

There are two key issues in the debate over the use of animals in xenotransplantation. The first is whether as a matter of principle, it is considered to be morally acceptable to use animals as organ or tissues sources. If it is agreed to be acceptable in principle, there are then questions to address regarding the welfare of animals within any xenotransplantation programme. Such questions will include consideration of how far animal welfare is compromised by procedures in, for example, transgenesis, the source animal breeding programme, the husbandry systems imposed by the need to maintain disease free animals, and the organ collection process. In other words whether high standards of humane care from birth to death of the animal can be ensured. A third important point is that xenotransplantation is still only a developing technology and a large number of animals will be used in the research and development programme. Animal experimentation is itself an emotive issue which will need to be addressed as an integral part of any discussion of the ethics of xenotransplantation.

Questions regarding the ethical acceptability of using animals

There are a series of ethical questions to consider: the ethics of animal use per se, the ethical acceptability of genetically manipulating animals, the use of particular species and the ethics of experimenting on animals in order to develop the technology.

Within society as a whole there is a spectrum of opinion regarding what it is acceptable to do to animals including whether it is morally acceptable or not to use them as a source of organs or tissues for transplants. This spectrum of views can be seen in the attitude surveys already noted in this report. It is important to consider all of these opinions, why they are held, and the criteria on which they are based, in determining policy on whether and how xenotransplantation should go ahead.

A logical discussion of the use of animals in xenotransplantation needs to take into account the existing relationship between animals and humans and what is currently considered acceptable in this respect. An animal rights philosophy would not allow any use of animals for any purpose unless it benefited the individual animal concerned. Most people in the world however do accept some use of animals, albeit in some cases limited to uses that do not require the animals’ suffering or death.

If some use is accepted, it is then necessary to determine what is, or is not, considered acceptable. People will express a variety of views on this question. Animals are already widely used within human societies for a variety of purposes. These include providing food, clothing, companionship, for entertainment and as ‘tools’ for research in the biomedical sciences. Their tissues, for example pig heart valves and skin, are also used for medical purposes. One view is that a line should be drawn under these current uses (and indeed that these should be further restricted) prohibiting further exploitation. Another view, and one which appears to predominate in the responses to surveys is that uses that may be of direct benefit to humans should be allowed, albeit strictly regulated and controlled with due regard to animal welfare.

There is an additional dimension to xenotransplantation over and above existing uses of animals, because many of the animals involved will be genetically engineered. Genetic engineering is different from other breeding technologies and is opposed by some people on moral, social or religious grounds on the principle that humans should not ‘play God’ and manipulate the genes (thus compromising the integrity) of any living organism, animal or plant.

The issue of species is a further topic for debate, i.e. whether it is more acceptable to use some species, such as pigs, as a source of organs rather than others, such as primates. Arguments on this point may be attitudinal and culture based (e.g. it may be considered acceptable to use pigs since they are already farmed for food; conversely it may not be considered unacceptable to use primates because they are not). They may also relate to animal welfare, i.e. whether it is considered possible to maintain the species in ‘clean’ conditions in a laboratory environment without this having a major impact on their welfare. There are also separate concerns about the disease risks associated with different species.

The focus of discussion to date has been on the use of pigs and primates as organ and tissue sources because most xenotransplantation research has involved these species. In the USA, it is considered ethically acceptable to use primates as organ sources (although recently there have been concerns about the level of disease risk involved). In the UK, the Kennedy Committee (which carried out an extensive review of the issue and reported in 1996) decided that it is acceptable to use pigs but not primates as organ and tissue sources. Several of the other countries in the survey express similar views.

A final issue is that the development of xenotransplantation technology to the point where it can be routinely used involves the use of animals in experiments which cause or have the potential to cause them pain, suffering and distress. The justification for such research will be the perceived lifesaving benefit of successful organ transplantation or cell therapy. However, if society as a whole rejects xenotransplantation, or cannot afford to implement it, then it can be argued that the lives of the many animals involved in this research will have been wasted.