Fecal inoculum can be used to determine the rate and extent of in vitro fermentation of dietary fiber sources across three lemur species that differ in dietary profile: Varecia variegata, Eulemur fulvus and Hapalemur griseus.

To estimate fermentative capacity among lemur species, four fiber substrates were tested across three species, Eulemur fulvus, Hapalemur griseus and Varecia variegata. The substrates, cellulose, beet pulp, citrus pulp and citrus pectin, ranged in composition from completely insoluble fiber (IF) to completely soluble fiber (SF), respectively. The lemurs consumed a nutritionally complete biscuit formulated for primates [85 g/100 g diet dry matter (DM)] and locally available produce (15 g/100 g diet DM). Feces were then collected and used to inoculate fermentation tubes prefilled with fiber substrates and an anaerobic growth medium. Dry matter disappearance (DMD), and acetate, propionate, butyrate, and total short-chain fatty acid (SCFA) production were measured in tubes subjected to 6, 12, 24 or 48 h of fermentation. Results were fitted to a logistic growth model. The maximal production (MP) time at which production or disappearance is at one-half maximum (t(50)) and the fermentation rate at 3 h were calculated. The maximal disappearance of DM differed among substrates (citrus pectin > citrus pulp > beet pulp; P < 0.0001) and species (E. fulvus > H. griseus > V. variegata; P < 0.001). V. variegata reached t(50) for acetate and total SCFA production faster than H. griseus or E. fulvus (P < 0.02). Three-hour production rates of acetate and total SCFA were also greater for V. variegata for citrus pulp and citrus pectin (P < 0.01). Few species differences were observed for beet pulp. Results provide evidence for differences in fermentative capacity and suggest that fiber solubility and fermentability should be considered when assessing the nutritional management of lemurs.