Serum concentrations of several nutrients were measured in 12 captive wild felid species including caracal (Felis caracal), cheetah (Acinonyx jubatus), cougar (Felis concolor), fishing cat (Felis viverrinus), leopard (Panthera pardus), lion (Panthera leo), ocelot (Felis pardalis), pallas cat (Felis manul), sand cat (Felis margarita), serval (Felis serval), snow leopard (Panthera uncia) and tiger (Panthera tigris). Diet information was collected for these animals from each participating zoo (Brookfield Zoo, Fort Worth Zoo, Lincoln Park Zoological Gardens and North Carolina Zoological Park). The nutritional composition of the diets at each institution met the probable dietary requirements for each species except for the pallas cat. Blood samples were collected from each animal (n = 69) and analyzed for lipids (total cholesterol, triacylglycerides, HDL cholesterol and LDL cholesterol), vitamin D metabolites [25-hydroxycholecalciferol (25(OH)D) and 1,25-dihydroxycholecalciferol (1,25(OH)₂D)], vitamin A (retinol, retinyl stearate and retinyl palmitate), vitamin E (α- and γ-tocopherol) and selected carotenoids. Species differences were found for all except triacylglycerides and 1,25(OH)₂D. Genus differences were found for retinol, retinyl palmitate, retinyl stearate, γ-tocopherol and β-carotene. Circulating nutrient concentrations for many of the species in this study have not been reported previously and most have not been compared with the animals' dietary intakes. The large number of animals analyzed provides a substantial base for comparing the serum nutrient concentrations of healthy animals, for both wild and captive exotic species.

Detrimental physiological effects due to stressors can contribute to the low captive success of primates. The objective of this research was to investigate the potential impact of diet composition on cortisol concentrations in feces and saliva in woolly (n=27) and spider monkeys (n=61). The research was conducted in three studies: the first investigated spider monkeys in the United States, the second investigated spider monkeys within Europe, and the third investigated woolly monkeys within Europe. Fecal cortisol in spider monkeys in US zoos varied (P=.07) from 30 to 66 ng/g. The zoo with the highest fecal cortisol also had the highest salivary cortisol (P≤.05). For European zoos, fecal cortisol differed between zoos for both spider and woolly monkeys (P≤.05). Spider monkeys had higher fecal cortisol than woolly monkeys (P≤.05). Zoos with the highest dietary carbohydrates, sugars, glucose, and fruit had the highest cortisol. Cortisol was highest for zoos that did not meet crude protein requirements and fed the lowest percentage of complete feeds and crude fiber. Differences among zoos in housing and diets may increase animal stress. The lifespan and reproductive success of captive primates could improve if stressors are reduced and dietary nutrients optimized.