KEEPING YOUR ELEPHANTS HAPPY

A new longitudinal study from ISWE members.

A basic understanding of wildlife endocrinology is critical to ensure the health and welfare of endangered species. Hormone analysis is a widely accepted tool for monitoring reproductive function and responses to stressors in captive and free-ranging animals. Understanding how factors in the captive environment affect individual animal wellbeing can be aided by long-term monitoring of reproductive and stress hormones, especially for large social mammals like elephants.

In one recently published work, conservation researchers from the Oregon Zoo reported a longitudinal study of reproductive and adrenal hormones in zoo-housed female Asian elephants. The study’s authors measured patterns of adrenal glucocorticoid (GC) activity and reproductive hormone status in association with major social changes. Cortisol and progesterone were initially measured using radio immunoassays (RIAs), until the RIAs were discontinued half-way through the study. Fortunately, the authors were able to continue the study by developing highly sensitive and specific non-radioactive enzyme immunoassays (EIAs) using Arbor Assays’ suite of custom assay development reagents. These reagents are made available as part of a long-standing collaboration between Arbor Assays and the International Society for Wildlife Endocrinology. Arbor Assays is proud to offer these valuable tools for biomarker analysis used by conservation researchers the world over.

This study helped to further understanding of the role of the stress response and ovarian function in Asian elephant physiology. Much like their human counterparts, the elephants exhibited substantial individuality in adrenal GC response to major social change. The authors concluded an integrated approach, using both behavioral and physiological measures, is necessary to fully understand how animals perceive and interact with changes or challenges in their environment, allowing social management improvement and welfare enhancement in both captive settings and free-ranging environments.