| The purpose of this research was to compare lemur species and characterize differences related to gastrointestinal morphology and physiology. Four lemur species that differ in feeding ecology, V. variegata (Vv), E. fulvus (Ef), P. verreauxi (Pv), and H. griseus (Hg), were compared. Morphological differences include the longer ratio of intestine length to body length for Pv (13.0:1) compared to other species (Vv, Ef, and Hg were all less than 5.0:1) and the shortened, blunt cecum and well haustrated colon unique to Hg. In vivo dry matter digestibility for animals fed an experimental diet (28% total dietary fiber) was 55.5% for Vv, 58.6% for Ef, 72.0% for Pv and 76.3% for Hg (Vv = Ef < Pv = Hg, p < 0.05, SEM 1.4%). In vivo insoluble fiber digestibility was 19.7% for Vv, 27.7% for Ef, 53.1% for Pv, and 62.3% for Hg (Vv = Ef < Pv = Hg, p < 0.05, SEM 3.4%). Soluble fiber (SF) digestibility showed the same trend. Although Vv was similar to Ef and lower than Hg for in vivo digestibility, 3-hour in vitro fermentation rates using fecal innoculum suggested Vv possessed a greater capacity for rapid fermentation of SF substrates (citrus pectin and citrus pulp). Maximum in vitro fermentation (48 h) did not differ across the three species. In vivo total tract transit time of chromium was 3.88 h for Vv, 3.15 h for Ef, 24.64 h for Pv, and 29.96 h for Hg (Vv = Ef < Pv < Hg, p<0.05, SEM 1.80 h). Gastric transit times of radio-opaque spheres (1.5mm) used to characterize transit within the tract were 0.25 h for Vv, 0.25–0.5 h for Ef, 1.0–2.0 h for Hg and 8.0–12.0 h for Pv. Intestinal transit time was 0.25–.75 h for Vv, 0.75–1.5 h for Ef, 12.0–16.0 h for Pv, and 22.0–23.0 h for Hg. These data add to available knowledge of primate feeding ecology and provide information useful for the nutritional management of lemurs. |
