SEASONAL VARIATION OF NUTRITIONAL HORMONES IN CAPTIVE FEMALE MOOSE

The health status of animals may be inferred from the patterns of hormonal concentrations and other chemical characteristics in blood samples. Baseline endocrine data representing the nutritional and reproductive condition of moose are currently unknown. In this study, we examined the seasonal patterns of 3 nutritional hormones (leptin, ghrelin, insulin-like growth factor-1) in 3 captive, non-pregnant female moose (Alces alces) fed a maintenance diet from November to August. Plasma concentrations for leptin, ghrelin, and IGF-1 averaged 1.36 [+ or -] 0.81 ng/mL, 0.229 [+ or -] 0.110 ng/mL, and 114.0 [+ or -] 30.5 ng/mL, respectively; only ghrelin displayed a seasonal change. Plasma ghrelin concentration was significantly elevated (P < 0.001) during winter months suggesting it may be sensitive to seasonal changes and indicative of nutritional status. Key Words: Alces alces, ghrelin, hormones, HPG axis, IGF-1, leptin, moose, reproduction, season
Northern latitudes are characterized by extreme seasonal differences in temperature, photoperiod, forage availability, and forage quality (Chapin et al. 1980, Risenhoover 1989). As a consequence, large herbivores such as moose [...]