PREDICTING BODY-FAT AND BODY-MASS IN MOOSE WITH ULTRASONOGRAPHY

Lipids are the primary energy store of the body and estimation of thes e reserves provides an indication of nutritional status in moose (Alce s alces). Estimates of total body fat enhance our understanding of rep roductive potential, survival rate, energy balance, and nutritional ca rrying capacity. We developed predictive equations of total body fat a nd body mass from ultrasonographic fat measurements for application in live animals. We detected a strong linear relationship (r(2) = 0.96) between ingesta-free body fat and rump fat thickness measured by ultra sonography. Rump fat thickness was measurable over a range of body fat levels (5.8-19.1%). Rump fat mass (r(2) = 0.92) and kidney fat mass ( r(2) = 0.95) were curvilinearly related to ingesta-free body fat level . For adult females, total length and chest girth were not related to body mass. Ingesta-free body fat, however, explained 81% of the variab ility in body mass, and ultrasonically measured rump far thickness pre dicted body mass (r(2) = 0.80).