Discussion Document prepared by the EUPREN Board of Management
1. Background
Housing of laboratory animals is to be considered at the December 1996 Multilateral Consultation of Parties to the European Convention for the Protection of Vertebrate Animals used for Experimental and Other Scientific Purposes. Although the number of non-human primates used for such purposes is relatively small, the issues which need to beaddressed in the discussion of their housing are particularly complex. There is, for example, a great diversity ofmorphological, physiological, psychological and social requirements for the different species of non-human primates used in research. The present paper has been prepared by EUPREN in advance of this Multilateral Consultation, in order to highlight the key issues which need to be considered in any discussion of housing for non-human primates. Over the next 3 months, a range of interested parties will be invited to comment (Annex 1).
It is clear that altering the detail of the European legislation on cage requirements could have wide-ranging implications. While such alterations offer considerable potential to enhance animal wellbeing, the financial investment required may lead to research being relocated to countries where welfare standards and control are less favourable than in Europe. It is therefore of critical importance to ensure that the legislative guidelines are based upon firm scientific foundations.
Many pre-existing guidelines are somewhat subjective in that they have been formulated on the basis of current practice, economic considerations and good intent. Relatively recent developments in remote and non-invasive monitoring enable the impact of different housing conditions to be assessed more objectively. The underpinning technologies and approaches for such studies were discussed at a EUPREN/EMRG Meeting on "The Implications of Non-invasive and Remote Monitoring Techniques for Non-human primate Research and Husbandry" (December 1995, Gottingen).
In view of the paucity of fundamental scientific information, there is an urgent need to collate available data, draw up a list of questions which need to be asked and agree upon the collaborative programmes which are required to provide the answers to these questions.
The progress of and recommendations which emerge from this document will be presented during the second EUPREN/EMRG Winter Workshop "The implications of housing and husbandry for scientific quality and wellbeing", Rome (25-27 November, 1996).
2. Factors for consideration
2.1 Scientific purpose
The purpose of the particular biological or biomedical research in which non-human primates are involved is an essential underlying consideration. The following example of two extreme situations illustrate the importance of addressing the scientific objectives of the study. In some pharmacological or toxicological investigations, there may be a need to administer test substances, collect blood samples and monitor aspects of metabolism over days. The type of procedures involved and the degree of human intervention required might be expected to require fundamentally different housing conditions from that appropriate to a long term study designed to investigate hierarchical behaviour in large social groups, with minimal human interaction. Although intuitively one might feel that it is always desirable to provide the largest cage with resources permit, it may well be that the impact of catching and restraining animals for interactive procedures, such as blood sampling, is more marked in animals housed in larger cages or social groups.
It is obvious that the standards and approaches to the provision of housing non-human primates being purpose-bred for subsequent use in research must be no less stringent.
It is proposed that, as a first step, a list should be compiled of the types of scientific and husbandry procedures and associated related scientific rationales, which are currently in use in different areas of research.
Such a list might establish the basis of a categorisation system. This would facilitate discussion of such issues as the scientific justification for single housing and could lead, ultimately, to standardization of studies involving non human primates.
2.2 Species needs and propensities
As well as factors such as scientific purpose, type and frequency of procedures/human intervention, laboratory housing must be sensitive to species-specific requirements. It is evident that factors such as sexual dimorphism, age, size and group dynamics need to be considered. Of course, captive housing always imposes limitations on the realisation of the behavioural repertoire which would be expected to exist of a particular species in the wild. Nonetheless, it is important to enable animals to exhibit as many aspects of their behavioural repertoire as practicable, within the context of the experimental situation.
While cage floor area and volume are obviously issues which must be considered in addresssing species needs and prospensities, they must not be considered as the sole determinants of housing quality. The wider considerations of cage design must be discussed and there are potential dangers in overemphasizing floor area and volume. Cage design should encompass features such as usable cage space, furniture, flexibility, configuration, and feeding provision.
2.3 Assessing the impact of laboratory housing
In order to obviate the danger of establishing contraproductive "pseudostandards" which may be adopted uncritically it is necessary to conduct well defined and tightly focused scientific studies to determine the impact of laboratory housing on the animals. The resulting information will have significant implications for subjective assessment of animal wellbeing as well as scientific quality.
A co-ordinated multidisciplinary approach will be required because of the inadvisability of reliance upon a single index to assess impact. It is likely that a combination of physiological, endocrinological, behavioural, immunological and biochemical factors will need to be considered. With this in mind, it will be necessary to agree priorities and standardise experimental protocols in order to enable information from diverse sources to be considered together. The establishment and maintenance of an accessible database for relevant existing data and information on proposed work as well as work in progress, will be a key feature.
As well as considering the impact of cage design, it will be important to address the relationship between laboratory housing and procedures conducted for scientific or husbandry purposes. For example, it would be of interest to investigate the implications of training animals to co-operate with experimental procedures or of varying the housing conditions for individual animals in situations where experimental protocols required more restricted caging for a small proportion of the study duration. Such information would be invaluable in the formulation of meaningful standards of animal care.&127;
3. Recommendations
Please give suggestions for considerations and discussion.
Annex 1
Those to whom the attached document will be circulated for discussion will include: