Investigation of Population-Level Effects of Copper Deficiency on Health and Reproductive Success of Hoofstock Populations at the San Diego Zoo Safari Park
The San Diego Zoo Safari Park (SDZSP) houses mixed hoofstock populations in large field exhibits with recognized copper deficiency and endoparasitism. Management strategies for these herd health problems use a variety of methods. Systematic analysis of laboratory results collected over the past 5 years has helped to evaluate previous—and refine future— treatment strategies.
To improve intervention, records of African species housed at SDZSP from 2013–2017 of Bovidae subfamilies Hippotraginae, Antilopinae, and the Bovinae tribe Tragelaphini were assessed retrospectively using ZIMS records (n=1425 individuals), laboratory data (n=5793 samples) for fecal parasite counts (n=708 individuals) and trace element screens (n=867 individuals), and pathology records for postmortem hepatic mineral measurements (n=394 individuals). The interactions between hypocuperism and animal health were evaluated to establish if populations with higher prevalences of copper deficiency also had lower reproductive success and neonatal survival.
Low serum copper levels were identified in nearly half of all individuals on trace element screen (Hippotraginae 47.13%, Antilopinae 45.28%, Tragelaphini 43.57%), with marginal or deficient hepatic copper less frequently noted on necropsy specimens (17.83%, 12.82%, 23.94%, respectively). Species‘birthrates (median 12.67/100 population/year), pre-wean mortality (median 43.24 deaths/100 live births) showed complex trends to association with herd copper status.
Females were significantly overrepresented with marginal or deficient hepatic copper (OR=2.05, p=0.03). Prioritizing copper supplementation to breeding females is one of several possible interventions highlighted to improve reproductive success and overall health in these populations.