Feed intake, digestion and passage of the proboscis monkey (Nasalis larvatus) in captivity

Abstract

ABSTRACT. Feeding trials were conducted with a troop of six proboscis monkeys (Nasalis larvatus) at the New York Zoological Park to quantify aspects of digestive physiology. Diets consumed comprised, on an as-fed basis, 55~ browse and green produce, 1107o fruit, 9070 commercial primate diets, 9070 root vegetables, and 1607o miscellaneous items. Total feed intake averaged 1207o of body mass; dry matter intake was 307o. Dry matter and plant cell wall disappearance exceeded 80070. Passage marker studies (three 6-day trials) revealed: transit time = 14 hr; mean passage time = 49 hr; and 5-8007o retention time = 52 hr. Digestion coefficients and retention times were greater than expected based on body size. These results might reflect the low fiber content of the diets fed, or alternatively, provide evidence that proboscis monkeys are efficient digesters of cell wall constituents.

The feeding ecology and activity budget of proboscis monkeys

“…Our results suggest that proboscis monkeys, which have a multichambered stomach similar to ruminants [Chivers, 1994], may devote a large proportion of their activity budget to resting to aid in the digestion of foods with high levels of cellulose as reported in other colobine species (e.g., Trachypithecus francoisi, 52 % of time spent resting) [Zhou et al, 2007]; Presbytis thomasi, 59% [Stanford, 1991a]; Colobus vellerosus, 59% [Teichroeb et al, 2003]; and C. guereza, 63% [Fashing, 2001a]. Feeding trials of captive proboscis monkeys support this suggestion because transit time (elapsed time from feeding to appearance of a marker in feces) is 14 hr and retention time (time between appearance of 5 and 80% of the markers) is 52 hr [Dierenfeld et al, 1992]. Further, as Fashing 2007 provides data supporting a positive relationship between time resting and body size among African colobines, proboscis monkeys, which are the largest colobines, appear to fit this pattern.…”

“…Yeager [1989] suggested that proboscis monkeys appear to enrich their diet with seeds. Although proboscis monkeys are probably efficient digesters of plant cell wall constituents [Dierenfeld et al, 1992], they may prefer unripe fruits and seeds, over leaves because they are composed of more easily digested carbohydrates than young leaves [Davies et al, 1988].…”

Nutrition: Chemical analysis and consistency of faeces produced by captive monkeys (françois langurs,trachypithecus françoisi) fed supplemental fibre

“…Our data point to an apparent digestibility of lignin of about 35%. Although it is generally accepted that lignin can neither be digested nor fermented, some authors have demonstrated that lignin apparently can be digested by leaf-eating monkeys (2,7,10). However, the observed digestibility of lignin has been ascribed to methodological error (9), as described by Watkins et al (10).Despite this, it cannot be excluded that leaf-eating monkeys have intestinal bacteria capable of breaking down lignin.…”

Gut Passage Rate in Guenons and Mangabeys: Another Indicator of a Flexible Feeding Niche?

“…They are closer to those found in more omnivorous species which are known to feed on over 40% leaves, such as Alouatta palliata and A. seniculus (MRT of 18-30 h; TT of 20.4 h) [5,6] or Nasalis larvatus (MRT of 49 h; TT of 14 h) [7], One cannot exclude the possibility that captivity modifies GPR, which is positively related to the proportion of dietary fibre in primates and other mammals [10,12,13]. However, it has been shown that captive mon keys fed on diets very similar to those of this study [5] had very different transit times de pending on the species.…”