O’GRADY, S.P.; DEARING, D.M: Digestive Efficiency in a Small Herbivorous Lizard

Assimilation of plant material has been well studied in large lizard herbivores that possess morphological adaptations specialized to a herbivorous diet. The efficiency with which small less specialized lizards assimilate plant material has been largely unstudied. We studied digestibility in Cnemidophorus murinus, a small (<100g) and unspecialized herbivorous lizard. Dry matter digesibility (DMD) and cellulose digestion were measured on lizards fed high (27% ADF) and low (17% ADF) fiber diets. There was no significant difference between low fiber (n=12) and high fiber (n=11) groups in either DMD (59% and 60%) or cellulose digestibility (82% and 87%). Both DMD and cellulose digestibility were comparable to larger more specialized herbivorous species and cellulose digestion was greater than that seen in herbivorous rodents (44%). These results suggest that additional adaptions may exist in Cnemidophorus murinus such as mutualistic gut flora. Future studies will examine the role of pinworms in fiber digestion.