DETERMINATION OF BLOOD MICROMINERAL AND FAT-SOLUBLE VITAMIN VALUES FOR WHITE-TAILED DEER
The current National Academies of Sciences, Engineering, and Medicine (NASEM) for micromineral and vitamin requirements for cervids are based on data collected from various small ruminant species. Lack of baseline requirements make diet formulation for high fenced, white-tailed deer (Odocoileis virginianus) herds particularly ambiguous. This study was to determine a baseline value for whole blood and serum micromineral and vitamin concentrations for white-tailed deer in an attempt to establish dietary requirements of microminerals and vitamins. Open does (n=223) were sampled using jugular venipuncture during fall breeding procedures. Captive-raised does housed at various high fenced ranches (n=3) throughout Texas were used, each with unique management strategies. Blood samples were analyzed for micromineral levels (Co, Cu, Fe, Mn, Mo, Se, and Zn) and fat-soluble metabolites (vitamin A, vitamin E, measured as α-tocopherol, and cholesterol). Age of the doe and ranch were used as main effects using the GLM procedure in SAS. Sampled averages were 6.31 ng/mL of Co, 1.04 µg/mL of Cu, 220.41 µg/mL of Fe, 4.43 ng/mL of Mn, 4.23 ng/mL of Mo, 172.48 ng/mL of Se, 0.54 µg/mL of Zn, 275.25 ng/mL of vitamin A, 1.80 µg/mL of vitamin E, and 79.61 of cholesterol. Ranch played an important role in micronutrient levels, with the exception of cholesterol (P=0.26). Micronutrient least squared means were also affected by age for Se, Zn, and vitamin E (P<.01). Pregnancy status was determined (n=93) via jugular venipuncture 30-37 d after breeding procedure. Females that became pregnant at initial breeding attempt had significantly higher serum Zn (P<.01) and vitamin E (P=0.03) levels. Factors such as feed, forage, soil, genetics, and health management protocols could explain the variance in values. The establishment of circulating blood micronutrient levels will serve as a baseline for future white-tailed deer nutrient requirement research and feed formulation.