Assessing Winter Dietary Quality in Bighorn Sheep via Fecal Nitrogen

Fecal indicators of nutritional status of wild ungulates are less constrained than blood or urine analyses. Thus, we assessed the potential for fecal nitrogen concentration to predict winter dietary quality for Rocky Mountain bighorn sheep (Ovis canadensis) in Wyoming. Dietary nitrogen concentration and percent in vitro dry matter digestibility increased linearly with increases in fecal nitrogen concentration for hand-plucked diets of wild sheep on 4 winter ranges and for tannin-free diets fed to 3 penned adult female bighorn sheep (2 were 1/8 mouflon [O. orientalis]). A linear'regression developed from field samples gathered in 2 winters accurately predicted winter dietary nitrogen concentrations using fecal nitrogen levels from other winters