Metabolic and Microbial Characterizations for the Gastrointestinal Digesta of the Zoo Colobus guereza

Abyssinian black-and-white colobus (Colobus guereza) inhabits west, central, and east Africa and lives in social groups in the rain forests. Colobus guereza has a unique foregut digestive system similar to that of ruminants and absorbs organic acids, including Short-Chain Fatty Acids (SCFAs), as energy sources derived from microbial fermentation of plant materials in the gastrointestinal tract. In this study, the gastrointestinal metabolic and microbial features of a male Colobus guereza singly housed in a zoo were characterized, and each digesta from each segment of the digestive tract was collected and subjected to biochemical, microbiome, and metagenome analyses. In this case report, high levels of acetate and propionate were observed in the foregut, while a relatively high level of lactate was detected in the small intestine. Moreover, in the hindgut and the feces, acetate was dominant compared to the other SCFAs. SCFAs analysis indicated that Colobus guereza obtains energy via SCFAs, especially acetate, fermentation in the foregut and hindgut. A metagenome analysis revealed that each part of the digestive tract of Colobus guereza has a unique microbiota. Similar to ruminants, Prevotella and Selenomonas were the dominant genera in the foregut, which may indicate microbial fermentation of plant materials in the foregut of Colobus guereza.

The diet and feeding behaviour of the black-and-white colobus (Colobus guereza) in the Kalinzu Forest, Uganda

One of the goals for primate feeding ecology is to understand the factors that affect inter- and intra-specific variations. Therefore, a detailed description of basic feeding ecology in as many populations and sites as possible is necessary and warrants further understanding. The black-and-white colobus (Colobus guereza) or guereza is widely distributed in Africa and is one of the well-studied colobines in terms of their feeding; they demonstrate considerable variation in their diets in response to local conditions. We studied the diet of a group of guerezas in the Kalinzu Forest, Uganda, for over 30 consecutive months using behavioural observation (4,308 h total), phenology, and vegetation surveys. A total of 31 plant species were consumed by the study group. This study group was predominantly folivorous; the majority of their feeding time was involved in feeding on young leaves (87%). However, during certain times of the year, fruits and seeds accounted for 45% of monthly feeding time. Young leaves of Celtis durandii were by far the most important food, which constituted 58% of the total feeding records. There was a significant increase in the consumption of fruits and flowers once young leaf availability was low, but their consumption of fruits did not significantly increase even when fruit availability was high. Their monthly dietary diversity increased as the number of available plants with young leaves declined, suggesting that much of the dietary diversity in the study group may be attributable to the young leaf portion of their diet. Our findings may help contribute to a better understanding of the dietary adaptations and feeding ecology of guerezas in response to local environmental conditions.