Jennifer L. Campbell

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 (t₅₀) 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 t₅₀ 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.

The nutrient content and intake of locally available North Carolina browse was evaluated for use as a supplement to a herbivorous primate diet of commercial biscuit and produce. Twice weekly from May to October 1997, total dietary intakes were determined for two groups of folivorous lemurs. Group I consisted of Propithecus diadema diadema (n = 1) and P. tattersalli (n = 1) and group II consisted of P. verreauxi coquereli (n = 3). Six pooled samples of the diet and weekly samples of three browse species, Rhus copallina, Albizia julibrissin, and Liquidamber styrachiflua were analyzed for dry matter, energy, fiber, and nitrogen content. Browse species were also analyzed for nonprotein nitrogen and acid‐insoluble nitrogen. Group average dry matter intakes were 37.1 ± 2.2% (mean ± SEM) and 49.7 ± 3.0% of amount offered for groups I and II, respectively. Browse contributed 40.7 ± 2.9% and 29.6 ± 2.4% of the total daily intake for groups I and II, respectively. Browse species differed (P < 0.05) for dry matter, energy, neutral detergent fiber, acid detergent fiber, cellulose, lignin, total nitrogen, nonprotein nitrogen, available nitrogen, and available protein. R. copallina and L. styrachiflua were similar in total nitrogen, available nitrogen, and nonprotein nitrogen; A. julibrissin was higher. L. styrachiflua was highest in lignin. Dry matter, acid detergent fiber, and lignin in browse samples increased seasonally (P < 0.05), whereas available protein decreased (P < 0.01). Animals were offered and consumed R. copallina most often, followed by A. julibrisson and L. styrachiflua. With the exception of R. copallina, animals generally consumed only the immature leaves, flowers, or seeds of species offered. Daily dry matter intake varied because of both browse offered and consumed and biscuit and produce diet consumed. Thus, increased fiber density can be a major benefit of browse use only when incorporated into the total diet with respect to species use, quantity of other diet ingredients offered, and targeted nutrient intakes. Zoo Biol 20:447–461, 2001.

The objective of this project was to better define the similarities and differences in gastrointestinal morphology present in lemur species. Measurements of the gastrointestinal tract of lemurs were obtained at necropsy from the captive population at Duke University Primate Center. Measurements of body length and weight, as well as gastrointestinal length, were recorded from five prosimian species: Propithecus tattersalli, Propithecus verreauxi, Varecia variegata, Hapalemur griseus, and Lemur catta. Photographs and measurements were used to obtain illustrations. Preliminary results suggest differences in gastrointestinal morphology among lemur species that coincide with differences in diet. Distinct sacculations in either the cecum or the colon were present for H. griseus, L. catta, P. verreauxi, and P. tattersalli, but not for V. variegata. The Propithecus specimens possessed a much greater ratio of gastrointestinal length to body length than the other three species. A short, blunt cecum and a shortened and sacculated colon were unique characteristics of the H. griseus specimens. These differences correlate well with a dietary shift from consumption of large amounts of structural plant cell wall (Propithecus sp.) to consumption of variable or moderate amounts (H. griseus, L. catta, and V. variegata). They also suggest that captive groups would benefit from further diet refinement in captivity.