Non-invasive assessment of physiological status: a 30-year contribution to primatology

Heistermann M.

Reproductive Biology Unit, German Primate Center, Göttingen, Germany, e-mail: mheistermann@dpz.eu

The ability to assess physiological status is important in helping to provide a more complete understanding of primate biology. Since primates are generally difficult to handle, potentially dangerous and sensitive to physical and social disruption, science and animal welfare as well as practical considerations emphasise the need for a non-invasive approach. Endocrine methods based on the measurement of hormones and their metabolites in urine and faeces have proven particularly useful since they do not require animal capture and/or restraint; samples can be collected on a frequent basis and for prolonged periods of time and the methods can be potentially applied to any given species. To date endocrine data exist for about 25-30% of the existing primate species and this information stems almost exclusively from the use of non-invasive techniques.

There are three main areas where these methodologies have substantially contributed to primatology: (1) facilitating captive management/breeding programmes, (2) extending the comparative database and (3) integrating physiology and behaviour in primate field research. The latter has led to a new discipline, field endocrinology, in which quantitative measures of physiological status are used to gauge the significance of observational data, thereby facilitating the testing of hypotheses concerning the adaptive value of behavioural and morphological traits. This has resulted in new insights into actions of physiological adaptation and behavioural and reproductive processes of wild primates in an evolutionary context. In this talk, the history and application of non-invasive endocrine assessment in primates will be reviewed. Examples from the three areas mentioned above will be presented to illustrate how non-invasive endocrine methodologies have contributed to primatology, with special reference to field-based research.