Protein quality of cottontail rabbit forages following rangeland disturbance

Abstract

Seasonal changes in the botanical composition of diets and protein quality of forages consumed by cottontail rabbits (Sylvilagus floridanus) were monitored on disturbed and undisturbed upland hardwood forest-tallgrass prairies in central Oklahoma. Our primary objective was to evaluate the seasonal dynamics of levels of selected amino acid nutrients in forages required for maintenance, growth, or reproduction, and explore bow these changes respond to habitat disturbance resulting from the use of herbicides and fire. Microhistological analyses of stomach digesta indiccated that summer diets were dominated by Panicum oligosanthes 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 between disturbed and undisturbed habitats were of little biological significance. Changes in the concentration of essential amino acids due to plant maturity were minimal in both summer and winter. Estimated levels of nitrogen and essential amino acids in reconstructed diets (based on food habits) appeared to be low, especially for the sulfur-containing amino acids (methionine + cystine) in summer.