RESUMO
We tested the effects of age, sex, and season on the nutritional strategies of a group of mountain gorillas (Gorilla beringei) in the Bwindi Impenetrable National Park, Uganda. Through observations of food intake of individual gorillas and nutritional analyses of dietary components over different seasons and environments, we estimated nutrient intake and evaluated diet adequacy. Our results suggest that the nutritional costs of reproduction and growth affect nutrient intake; growing juveniles and adult females ate more food and more protein per kilogram of metabolic body mass than did silverbacks. The diets of silverback males, adult females, and juveniles contained similar concentrations of protein, fiber, and sugar, indicating that adult females and juveniles did not select higher protein foods than silverbacks but rather consumed more dry matter to ingest more protein. Juveniles consumed more minerals (Ca, P, Mg, K, Fe, Zn, Mn, Mo) per kilogram of body mass than adult females and silverback males, and juveniles consumed diets with higher concentrations of phosphorous, iron, and zinc, indicating that the foods they ate contained higher concentrations of these minerals. Seasonally, the amount of food consumed on a dry weight basis did not vary, but with increased frugivory, dietary concentrations of protein and fiber decreased and those of water-soluble carbohydrates increased. Energy intake did not change over the year. With the exception of sodium, gorillas ate diets that exceeded human nutrient requirements. A better understanding of the relative importance of food quantity and quality for different age-sex classes provides insights into the ways in which gorillas may be limited by food resources when faced with environmental heterogeneity.
Assuntos
Dieta , Ecossistema , Gorilla gorilla/fisiologia , Estado Nutricional , Ração Animal , Animais , Ingestão de Energia , Feminino , Gorilla gorilla/crescimento & desenvolvimento , Masculino , Plantas , Estações do Ano , UgandaRESUMO
Foods eaten by gorillas (Gorilla beringei) in Bwindi Impenetrable National Park (BINP), Uganda, were analyzed for their nutrient content. The goal of the study was to assess the amounts of fiber, protein, and sugars in the foods eaten by the Bwindi gorillas, and to determine whether condensed tannins and cyanide are present in these foods. A total of 127 food plant parts representing 84 plant species eaten by two groups of Bwindi gorillas were collected, processed, and analyzed for their chemical contents. The Bwindi gorilla ate foods that contain 2-28% crude protein (CP), 21-88% neutral detergent fiber (NDF), 14-60% acid detergent fiber (ADF), 2-42% acid detergent lignin (ADL), and =1-50% water-soluble carbohydrates (WSC) on a dry matter (DM) basis. Moisture in these foods ranged from 7% to 96%. Approximately 35% of the foods analyzed contained condensed tannins, and two foods contained cyanogenic glycosides. This is the first detailed report regarding the nutritional chemistry of gorilla foods in Bwindi, many of which are also eaten by other primates. This unique data set adds to our knowledge about the nutritional composition of foods eaten by gorillas across habitats, is useful for understanding aspects of feeding behavior, and provides valuable comparative data for optimizing the diets of gorillas ex situ.
Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Análise de Alimentos , Gorilla gorilla/fisiologia , Plantas Comestíveis/química , Animais , Carboidratos da Dieta/análise , Fibras na Dieta/análise , Proteínas Alimentares/análise , Comportamento Alimentar , Uganda , Água/análiseRESUMO
OBJECTIVE: To determine whether equine motor neuron disease (EMND) could be induced in adult horses fed a diet low in vitamin E and high in copper and iron. ANIMALS: 59 healthy adult horses. PROCEDURE: Horses in the experimental group (n = 8) were confined to a dirt lot and fed a concentrate low in vitamin E and high in iron and copper in addition to free-choice grass hay that had been stored for 1 year. Control horses (n = 51) were fed a concentrate containing National Research Council-recommended amounts of copper, iron, and vitamin E. The hay fed to control horses was the same as that fed to experimental horses, but it had not been subjected to prolonged storage. Control horses had seasonal access to pasture, whereas experimental horses had no access to pasture. Horses that developed clinical signs of EMND were euthanatized along with an age-matched control horse to determine differences in hepatic concentrations of vitamin E, vitamin A, copper, iron, and selenium. RESULTS: 4 experimental horses developed clinical signs of EMND. Plasma concentrations of vitamin E decreased in all 8 experimental horses. There were no significant changes in plasma concentrations of vitamin A, selenium, and copper or serum concentrations of ferritin. There were no significant differences in those analytes between experimental horses with EMND and experimental horses that did not develop EMND. No control horses developed EMND. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that lack of access to pasture, dietary deficiency of vitamin E, or excessive dietary copper are likely risk factors for EMND.