Long-term storage effects in steroid metabolite extracts from baboon (Papio sp.) faeces – a comparison of three commonly applied storage methods

1. The measurement of steroid hormone metabolites from faeces in wild animal populations is a powerful, non-invasive tool in behavioural endocrinology of all major vertebrate taxa. However, because such research is often done in remote areas with limited infrastructure, storage of samples for hormone analysis over long periods at high temperature is a critical issue in field endocrinology. Previous studies have indicated that storage of alcoholic faecal extracts is more reliable than storage of unprocessed faeces if no freezer is available, but a standard method has not been established yet. 2. We tested the validity of three commonly applied storage conditions - liquid extracts, dried extracts, and extracts placed on solid phase extraction (SPE)-cartridges - to preserve concentrations of glucocorticoid and androgen metabolites from faecal extracts of olive baboons (Papio anubis) at high temperature over one year. 3. Temporal variation in concentrations was detected for all metabolites ...