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National Research Council (US) Institute for Laboratory Animal Research. The Development of Science-based Guidelines for Laboratory Animal Care: Proceedings of the November 2003 International Workshop. Washington (DC): National Academies Press (US); 2004.

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The Development of Science-based Guidelines for Laboratory Animal Care: Proceedings of the November 2003 International Workshop.

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Assessment of Animal Housing Needs in the Research Setting Using a Peer-reviewed Literature Approach: Dogs and Cats

Graham Moore


A previous presentation (De Leeuw 2004) provided an outline of the Council of Europe (CoE) and the background of its process to revise Appendix A (guidelines for accommodation and care) of Convention ETS 123 (European Convention for the Protection of Vertebrate Animals used for Experimental and Other Scientific Purposes) of 1986. In this presentation, I will describe how the Council of Europe's requirements have been applied to the preparation of draft guidance on the accommodation and care of dogs and cats.


In 1997, the CoE adopted a resolution on accommodation and care of vertebrate animals used for experimental and other scientific purposes (Council of Europe 1997). It had been generally agreed by the CoE that the existing “Guidelines for accommodation and care of animals” presented in Appendix A of Convention ETS 123 had proved very useful and had been applied widely within Europe. However, it was also acknowledged that scientific knowledge and experience had progressed since 1986 and the entry into force of the Convention, such that a review of the guidelines was necessary.

The resolution stipulated that the new proposals should be divided into General and Species-Specific recommendations and also indicated key areas to which attention should be given. It further identified the way in which guidance should be prepared. Expert Groups, with representation from nominees of observer nongovernmental organizations of the Council of Europe but not of the national authorities, were to be set up to prepare proposals on the main groups of species covered by the Convention. These proposals would then be submitted to a Working Party for comment, amendment, and endorsement. Membership of the Working Party comprised representatives of the national authorities of the CoE member states, together with observers from a wide range of concerned nongovernmental organizations. A Drafting Group assisted in the work of the Expert Groups and of the Working Party. Once the Working Party agreed on all proposals from the Expert Groups, they would be received by a CoE Multilateral Consultation for any further discussion and approval, before being submitted to the Committee of Ministers for final approval.

It is important to note that the status of Appendix Ais “guidance” and the guidelines are not mandatory. However, it was generally considered by the Expert Groups that these should be regarded as minimum requirements.


Initially, only four Expert Groups had been established, on (1) Rodents and Rabbits, (2) Dogs and Cats, (3) Nonhuman Primates, and (4) Pigs and Minipigs. These four groups were given the task of preparing Species-Specific proposals, with the General Part of the new proposals, including provisions common to all species covered, being drafted with input from all four groups. The Working Party later decided to add additional species covered by the Convention to the list of those already to be covered by the revision; thus, the number of groups grew from four to eight. Furthermore, the Pigs and Minipigs group was expanded to cover all farm animal species, and ferrets were added to the Dogs and Cats group.

Currently, the General Section and Species-Specific proposals for Rodents, Rabbits, Dogs, Cats, and Ferrets have been finalized by the Working Party. Those for other species have not yet been finalized, although those for Nonhuman Primates, Birds, and Amphibians are at a very advanced stage.


As with all of the Expert Groups, there was a broad-based representation drawn from the observer nongovernmental organizations of the CoE. The membership of the Expert Group on Dogs and Cats comprised one representative from each of the following: the Eurogroup for Animal Welfare, the European Federation of Pharmaceutical Industries and Associations (EFPIA), the Federation of Laboratory Animal Breeders Associations (FELABA), the Federation of Veterinarians in Europe (FVE), and the International Society for Applied Ethology (ISAE). Meetings were coordinated and chaired by a representative of the Federation of European Laboratory Animal Science Associations (FELASA). A second ISAE representative was subsequently added because more input on cat ethology was deemed necessary. This membership was thought to provide a broad spread of expertise and opinion, which would result in the formulation of an expert view on minimum standards for these species.

It was decided at an early stage that the group would work primarily on the basis of face-to-face meetings (held in London or Brussels), with e-mail communication between meetings. Additional input would be sought as necessary from within represented organizations or from other experts. The Coordinator of the Group, together with one or more members, attended all meetings of the Working Party in Strasbourg to present the Group's proposals, discuss their content and answer questions, and refer matters back to the Group as appropriate.


The CoE stipulated the provision of proposals for a General Section and for Species-Specific Sections (called Part A). It also requested a supporting explanatory and referenced text (Part B) for each of the sections.

Groups were directed to pay special attention to enrichment of the environment, particularly in relation to social interactions, activity-related use of the space, and provision of appropriate stimuli and materials. Proposals were to be based on science-based information when it was available, and otherwise on practical experience and good or “best” practice. Where appropriate, Expert Groups were given the task of identifying areas in which additional research would be desirable.

The Expert Group on Dogs and Cats considered these areas and paid attention to existing guidance documents, such as the current Appendix A, UK Home Office guidance (1989 (1995), and the ILAR Guide for the Care and Use of Laboratory Animals (NRC 1996). Some significant variations were found in these recommendations, particularly those for space requirements and for some environmental parameters. It was therefore decided that where robust science-based information was not available, proposals would be based primarily on an examination of the animals' physiological and ethological needs, taking into account the current views on good/best practice and the inevitable constraints of a research environment.

Species-Specific Section—Subject Headings

The species-specific sections for dogs and cats covered the following:

  • Preamble
  • Introduction
  • The environment and its control
    • Ventilation
    • Temperature
    • Humidity
    • Lighting
    • Noise
    • Alarm systems
  • Health
  • Housing and enrichment
    • Housing
    • Early socialization with conspecifics and humans
    • Enrichment
    • Animal enclosures
      • Outside runs (dogs only)
      • Dimensions
      • Flooring
  • Feeding
  • Watering
  • Substrate, litter, bedding, and nesting material
  • Cleaning
  • Handling (cats only)
  • Humane killing
  • Records
  • Identification

For subject headings that were common to all species-specific sections, the Group decided no proposals were necessary other than those already contained in the General Section. These headings are shown in italics in the list above. Additional headings in the General Section were Definitions; Physical Facilities; Education and Training; Care (incorporating Health, Capture from the wild, and Transport); and Quarantine, acclimatization, and isolation.

Space does not permit detailing all of these recommendations; however, some examples drawn from the proposals on housing and enrichment and on dimensions and flooring provide an indication of key aspects of the proposals. It should be noted that some variation from these recommendations is permitted if it is justified on scientific, veterinary, husbandry, or other welfare grounds. It was the view of the Expert Group that justification on scientific grounds should be specifically authorized by each nation.

Specific Proposals Relating to Dogs

The dog is an inquisitive and highly social animal. The overriding principle is therefore the need to encourage and motivate social housing while providing a complex physical and social environment within the available space. The need for social housing is supported by the association of long-term single housing and social isolation with a range of behavioral disturbances (Hetts and others 1992). The benefits of enriching the environment—both social and physical—have been reported by Hubrecht (1993, 1995) and DeLuca and Kranda (1992). Social interactions are particularly important in dogs from 4 to 20 weeks of age, when social behavior is developing (Scott and Fuller 1965; Scott and others 1974; Wright 1983).

Some key proposals therefore were that:

  • Animals should be held in socially harmonious groups with a minimum of two (i.e., a pair).
  • Social contacts of puppies between littermates and with humans should be encouraged, particularly during the key socialization period of 4 to 20 weeks of age.
  • Separate areas should be provided within pens for different activities (e.g., by the use of raised platforms and pen divisions), should allow for some privacy, and should enable the dogs to exercise some control over their social interactions.
  • Physical enrichment items such as dog treats and toys afford welfare benefits, particularly where they meet the dog's chewing behavior and are adequately monitored.

There is a considerable divergence of views on the amount of space necessary for each dog in a pen or other enclosure. The view taken by the Expert Group was that the minimum space allowances should take full account of the key points described above and listed in Table 1.

TABLE 1. Minimum Space Allowances Necessary to Encourage Social Housing and Permit Adequate Enrichment of the Environment Regarding Pen Subdivision and Other Factors.


Minimum Space Allowances Necessary to Encourage Social Housing and Permit Adequate Enrichment of the Environment Regarding Pen Subdivision and Other Factors.

These recommendations were based on the requirements of beagles. For other breeds, space allowances should be determined in consultation with veterinary staff and the national authority. It can be seen from Table 1 that although the smallest pen in which any beagle may be kept should be 4 m2, a basic pen unit of 2 m2 would allow considerable flexibility.

In deciding space allowances for postweaned stock, the Expert Group took account of the particular needs within commercial breeding establishments and proposed the data that appear in Table 2.

TABLE 2. Space Allowances for Postweaned Dogs.


Space Allowances for Postweaned Dogs.

There are differing views on the type of flooring appropriate for dogs, and this topic was discussed in detail at the Berlin Workshop (1993). The Expert Group's view was that the preferred flooring for dogs was solid and continuous, with a smooth but nonslip finish, and that open flooring systems such as grids or mesh should be avoided. However, it was decided that there was not sufficient evidence to prohibit open flooring systems, provided they were appropriately designed and constructed, avoided pain, injury, or distress, and allowed the animals to express normal behaviors. Nevertheless, all dogs—on whatever flooring system— should be provided with a comfortable solid resting area within their enclosure. Furthermore, preweaned pups and periparturient and suckling bitches should not be held on an open floor system.

Specific Proposals Relating to Cats

The proposals on housing and enrichment and on dimensions and flooring for cats took account of consideration similar to those for dogs (Table 3). It was recognized that cats have a strong tendency to learn social behavior, even though they are descended from a solitary species. They do not, for example, form distinct dominance hierarchies. However, it was also recognized that the process of forming social relationships may be stressful and that interpreting visible signs of stress may be more difficult than in dogs.

TABLE 3. Summarized Proposals of Cage Space Requirements for Cats.


Summarized Proposals of Cage Space Requirements for Cats.

Key proposals for cats were that:

  • They should be socially housed where appropriate; however, social stress in all pair- or group-housed animals should be monitored at least weekly using an established behavioral and/or physiological stress scoring system (e.g., Kessler and Turner 1997).
  • Social contacts with littermates and with humans is essential between 2 and 8 weeks of age to encourage the development of social behavior.
  • Vertical space should be well utilized and is particularly valuable for cats to provide vantage points, allow for climbing, and allow increased control over their social interactions.
  • Pseudopredatory and play behavior should be encouraged, both by providing toys and by interacting with humans. Toys should be changed on a regular basis to avoid familiarity.

As with dogs, minimum space allowances for cats took account of the requirement for social housing, for adequate enrichment of the environment by means of subdivisions and provision of enrichment items, and for sufficient separation of areas for different purposes, such as feeding and litter trays.

The question of solid or open flooring was considered at the Berlin Workshop (1993). The recommendations agreed by the CoE Working Party were similar for cats and dogs, although the Expert Group decided that cats require a solid floor and should not be kept on open flooring at any time unless for specific scientific purposes and as authorized by the national authority. The provision of a comfortable resting place (e.g., raised, partly enclosed bed with bedding material) was considered particularly important for this species.


Guidance on accommodation and care will probably never achieve universal agreement or acceptance, particularly with domesticated/pet species such as dogs and cats, on which a very large number of people would probably claim to be experts but within which there would be a wide range of opinions. There is minimal research-based information available specifically on housing needs, and the Expert Group was able to identify certain areas where focused research would be of benefit (e.g., the relation between minimum space and the quality of the space provided). The possible impact of certain proposals on science also may warrant further study.

Nevertheless, there is a considerable body of data in relation to these species' physiological and ethological needs, which formed the starting point for the Expert Group's discussions. Identifying these needs and then adopting an outcomes-based approach would seem to meet the call for recommendations to be driven by science. Certainly they were driven by the four principles of published data where available, scientific principles, expert opinion, and experience. The inclusion of representation from animal welfare or protection groups provides an example of how the research and animal protection communities can work together to improve animal welfare while recognizing the needs of science. It also enhances political and public acceptability of the process.

The procedure to revise the guidelines that have been adopted by the Council of Europe is a stamina-sapping one, having already occupied more than 5 years. However, this is both a reflection of the extensive and detailed discussion that has taken place and a recognition of the broad range of expert opinions involved. Yet knowledge gained by further research and scientific evidence, as well as changing views on what is currently regarded as good or best practice, will mean that the accommodation and care that should be provided animals in research in the future will make additional revisions of the guidance necessary.


I am very grateful to all members of the Council of Europe's Expert Group on Dogs and Cats for their considerable input related to the proposals. The discussions were held at all times in a positive, constructive, and good-humored way. I am also most grateful to ILAR for inviting me to speak at this international workshop.


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Copyright © 2004, National Academy of Sciences.
Bookshelf ID: NBK25389
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