PROTEIN-QUALITY OF COTTONTAIL RABBIT FORAGES FOLLOWING RANGELAND DISTURBANCE

Seasonal changes in the botanical composition of diets and protein qua lity of forages consumed by cottontail rabbits (Sylvilagus floridanus) were monitored on disturbed and undisturbed upland hardwood forest-ta llgrass prairies in central Oklahoma. Our primary objective was to eva luate the seasonal dynamics of levels of selected amino acid nutrients in forages required for maintenance, growth, or reproduction, and exp lore how these changes respond to habitat disturbance resulting from t he use of herbicides and fire. Microhistological analyses of stomach d igesta indicated that summer diets were dominated by Panicum oligosant hes Schultes, Croton spp., and Sporobolus asper (Michx.) Kunth; winter diets were dominated by Bromus spp., P. oligosanthes, and Antennaria spp. Differences in the botanical composition and quality of diets bet ween disturbed and undisturbed habitats were of little biological sign ificance. Change in the concentration of essential amino acids due to plant maturity were minimal in both summer and winter. Estimated level s of nitrogen and essential amino acids in reconstructed diets (based on food habits) appeared to be low, especially for the sulfur-containi ng amino acids (methionine + cystine) in summer.