The increased requirement for combined chronic toxicity and fertility assessment of biologics has led to greater use of sexually mature non-human primates. Older animals have different needs compared to the younger, adolescent animals with which we are used to working. In addition, the establishment of sexual maturity requires additional parameter measurements, such as assessment of menstrual cycling, hormone analyses, and seminology. Changes in caging are required to reflect the social hierarchy inherent with the interaction of older primates, especially since subordinate animals mature later than their dominant peers. Provision of complex environmental stimuli also becomes a greater necessity. Due to the increased size and weight of older primates, handling becomes more of a potential source of stress and injury, to both animals and their handlers. Differential criteria for assessment of sexual maturity in primates are discussed.
Source: Developments in Life Sciences