A survey of serum and dietary carotenoids in captive wild animals

Accumulation of carotenoids varies greatly among animal species and is not fully characterized. Circulating carotenoid concentration data in captive w ild animals are limited and may be useful for their management. Serum carot enoid concentrations and dietary intakes were surveyed and the extent of ac cumulation categorized for 76 species of captive wild animals at Brookfield Zoo. Blood samples were obtained opportunistically from 275 individual ani mals immobilized for a variety of reasons; serum was analyzed for alpha- an d beta-carotene, lutein + zeaxanthin, lycopene, beta-cryptoxanthin and cant haxanthin. Total carotenoid content of diets was calculated from tables and chemical analyses of commonly consumed dietary components. Diets were cate gorized as low, moderate or high in carotenoid content as were total serum carotenoid concentrations. animals were classified as unknown, high, modera te or low (non-) accumulators of dietary cartenoids. Nonaccumulators had to tal serum carotenoid concentrations of 0-101 nmol/L, whereas accumulators h ad concentrations that ranged widely, from 225 to 35,351 nmol/L. Primates w ere uniquely distinguished by the widest range of type and concentration of carotenoids in their sera. Most were classified as high to moderate accumu lators. Felids had high accumulation of beta-carotene regardless of dietary intake, whereas a wide range of exotic birds accumulated only the xanthoph ylls, lutein + zeaxanthin, canthaxanthin or cryptoxanthin. The exotic ungul ates, with the exception of the bovids, had negligible or nondetectable car otenoid serum concentrations despite moderate intakes. Bovids accumulated o nly beta-carotene despite moderately high lutein + zeaxanthin intakes. Wild captive species demonstrated a wide variety of carotenoid accumulation pat terns, which could be exploited to answer remaining questions concerning ca rotenoid metabolism and function.