CHANGES IN BODY COMPOSITION OF MOOSE DURING WINTER

Abstract

Nine adult moose (Alces alces) were assigned to one of 3 treatments in 2 separate trials. In trial 1, 3 treatment groups of 3 moose were fed a pelleted diet ad libitum or at 85% and 70% of ad libitum intake. During trial 2, 3 treatment groups of moose were fed ad libitum intake one of 3 pelleted diets containing a metabolizable energy (ME) content of 2.4, 2.1, and 1.8 kcal/g dry matter. Estimates of body composition were determined with tritiated water. In trail 1, female moose fed restricted quantities (85% or 70% of ad libitum intake) of food lost weight and fat at faster rates than moose fed at libitum. The percentage change in kg of fate from pretrial measurements in October until the end of the trail in April was 33.0%, 26.8%, and -57.2% for the high-to-low intake treatments, respectively. Male moose were excluded from analysis because of differences in the dynamics of body composition over time, and reasons are discussed. In trial 2, both male and female moose fed 1.8 and 2.1 kcals ME compensated for lower levels of available energy by increasing dry matter intake. Fat dynamics were not different (P > 0.05) among the treatments but were different (P < 0.05) over time. Change in the energy pool indicated that fat catabolism/metabolism contributed about 94.7-100% of the calories, although the variation was high. Estimates of body composition based on the tritiated-water technique were variable, and reasons are discussed.