dures, and they should be evaluated when conditions appear to be causing unacceptable stress.
Husbandry practices that contribute to distress should be corrected. The environment should be well defined and controlled (e.g., established temperature, humidity, ventilation, and illumination standards should be met, noise reduced, etc.). The housing, feeding, and care of laboratory animals should be appropriate for the species to promote their health and well-being. Personnel that care for and use animals should be adequately trained. Generally, these issues are not a major source of disagreement. The attainment of well-being, however, might require consideration of other factors, such as environmental enrichment and socialization.
Given the present state of knowledge, specific recommendations and guidelines are necessarily tentative. It is possible, however, to indicate the kinds of questions that are reasonable to consider when evaluating environmental sources of stress and distress that can be addressed through changes in husbandry practices. With the discussion of the six ecologic dimensions in Chapter 3 as a guide, we offer the following questions as examples for use in assessing the adequacy of husbandry practices.
Should the animal be housed alone or with others?
Does the animal belong to a species that is mainly solitary (such as cats) or that normally lives in social groups (such as dogs, nonhuman primates, and most rodents)?
Is the animal is housed with others, is continuous group living characteristic of the species (such as sheep), or are seasonal or other cyclic variations in sociability the rule (such as hamsters)?
If animals are housed in groups, are the number of animals and available space such as to prevent crowding?
Are the members of the group compatible? Are some animals being picked on or always causing trouble?
Are the numbers or proportions of adult males, adult females, and immature animals in the group appropriate?
Have all members of the group been adequately socialized with conspecifics during their early development?
Are the animals familiar with each other?
Is fighting or aggressive dominance a normal feature of social relationships in the species? If so, are physical arrangements—such as the volume of space, the location of barriers, and the placement of food sources—appropriate to minimize aggression?
If offspring are to be separated from parents, when should this occur, which sex normally leaves the family group, and at what age? What provisions have been made to keep stress from becoming extreme?