Limited nutritional information exists on diets of free-ranging orangutans, Pongo abelii and P. pygmaeus. Although they are classified as frugivores, the chemical composition of their diet and their gastrointestinal anatomy suggest that they rely on fiber fermentation for a substantial portion of energy. However, the extent to which they can ferment fiber is not known. Continuous culture systems, inoculated with orangutan fecal bacteria, were established to determine the fiber-digesting capacity of orangutan hindgut microflora. The cultures received one of four treatments: soybean hulls, ground corncobs, corn starch, or no food. Neither dry matter nor neutral detergent fiber digestibilities differed significantly among treatments. However, neutral detergent fiber digestibilities were high for both the soybean hull (88.4%) and ground corncob (86.1%) treatments, indicating that the microflora had a strong fibrolytic capability. To determine whether the same fiber-degrading capacity occurred in vivo, two adult orangutans and one juvenile were fed four gel-matrix diets containing soybean hulls, ground corncobs, or ground primate biscuits. Neutral detergent fiber concentrations (dry matter basis) of the gel matrices were 52.9% with soybean hulls, 46.8% and 63.7% with ground corncobs, and 31.3% with ground primate biscuits. A fifth diet consisted of primate biscuits with 27.3% neutral detergent fiber (dry matter basis) and was considered the baseline diet. Neutral detergent fiber digestibility (74.5%) was greatest (P < 0.05) for the soybean hull gel diet and least (57.5% and 45.0%, respectively; P < 0.05) for the 63.7% neutral detergent fiber (dry matter basis) corncob gel diet and the baseline primate biscuit diet. Total volatile fatty acid concentrations in orangutan feces were not significantly different among diets; however, molar proportions of acetic, propionic, and butyric acid differed (P < 0.05) among diets. The results from both studies indicated that orangutans are capable of extensive fiber fermentation.
Quantifying circulating nutrient concentrations in sera of free-ranging subjects will help to establish a basis from which we can evaluate the nutritional status and needs of the captive population. We collected serum samples from 26 free-ranging black-and-gold howlers (Alouatta caraya) in San Cayetano forest in northern Argentina. We analyzed them for concentrations of lipoproteins; amino Int J Primatol (acids; vitamins A, D, and E; carotenoids; and minerals. There are a few significant differences between sexes in concentrations of high-density lipoprotein cholesterol, certain amino acids, vitamin E, lutein + zeaxanthin, and copper. Most nutritional parameters are similar to the ones measured in free-ranging Mexican mantled howlers (Alouatta palliata mexicana) and in captive New World primates (NWPs). Carotenoid, vitamin D, and phosphorus concentrations are the exceptions. Carotenoid concentrations are higher in free-ranging Alouatta caraya than reported for other free-ranging and captive species. Vitamin D concentrations are 14 times greater in the free-ranging black-and-gold howlers than in captive NWPs. Phosphorus concentrations are also higher than expected and higher than typically occur in captive primates, leading to a 1:1.6 calcium:phosphorus ratio. Because we based our study on a small number of free-ranging howlers, additional samples from different regions and throughout the year would better define desirable nutritional parameters for captive howlers.
Previously reported values for produce items often reflect only the human edible portion although animals generally eat the entire item. Produce can comprise a significant proportion of a captive, exotic animal's diet; therefore, nutrient values based on whole items will enable a more accurate diet formulation. Whole produce items, including fruits, vegetables, and leafy green vegetables, were analyzed for dry matter, neutral detergent fiber, acid detergent fiber, crude protein, fat, ash, pectin, fructan, and free sugar concentrations. The free sugars were typed and quantified. As expected, the produce contained low concentrations of neutral detergent fiber, averaging 13.4% for fruits, 18.8% for vegetables, and 21.5% for leafy green vegetables/other items on a 100% dry matter basis. Produce ranged substantially in structural and nonstructural carbohydrates, protein, fat, and free-sugar concentration. Free-sugar ratios of glucose, fructose, and sucrose varied among items. This information can be used for more accurate formulation of zoological diets.
Cholesterol concentrations in captive gorillas and orangutans vary widely within species and average approximately 244 mg/dl for gorillas and 169 mg/dl for orangutans as published previously. The International Species Inventory System reports higher concentrations of 275 and 199 mg/dl for gorillas and orangutans, respectively. It is unknown whether these values were typical, influenced by captive management, or both. To answer this question, banked serum samples from free-ranging mountain gorillas (Gorilla beringei), western lowland gorillas (Gorilla gorilla gorilla), and Bornean orangutans (Pongo pygmaeus) were analyzed for total cholesterol, triglyceride, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol concentrations. Mountain gorillas did not differ significantly from free-ranging western lowland gorillas in cholesterol, triglyceride, high-density lipoprotein cholesterol, or low-density lipoprotein cholesterol concentrations, indicating mountain gorilla values could be a model for western lowland gorillas. Captive gorilla total cholesterol and low-density lipoprotein cholesterol concentrations were significantly higher (P < 0.05) than in free-ranging groups. Triglyceride concentrations for captive gorillas were significantly higher (P < 0.05) than the male mountain and western lowland gorillas, but they were not significantly different from the female mountain gorillas. Captive orangutan total cholesterol concentrations were only higher (P < 0.05) than the free-ranging female orangutans, whereas captive orangutan low-density lipoprotein cholesterol concentrations were significantly higher (P < 0.05) than both free-ranging male and female orangutans. Calculated and measured low-density lipoprotein cholesterol concentrations were compared for all free-ranging animals and were significantly different (P < 0.05) for all groups, indicating Friedewald's equation for calculating low-density lipoprotein cholesterol is not appropriate for use with nonfasted apes. The higher total cholesterol and low-density lipoprotein cholesterol concentrations in captive apes may predispose them to cardiovascular disease and might be attributed to diets, limited energy expenditure, and genetics.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.