Nutritional Effects on Thyroid Activity and Blood of White-tailed Deer

Seal, U; Verme, L; Ozoga, J; Erickson, A

Two groups of penned, pregnant white-tailed deer ( Odocoileus virginianus) on high and moderate planes of nutrition were studied in December, March, and April. Two additional groups, one trapped from a deeryard and another from a herd in an enclosure, were studied in March and April. Twenty-seven assays including hematology, chemistry, and hormones were performed on each blood sample to provide a composite picture of the metabolite response of the deer to winter and to nutritional deprivation. Statistically significant (P < 0.05) seasonal decreases in the group on the high diet were found for weight,potassium, and serum urea nitrogen. Significant increases were found for hemoglobin, packed cell volume, erythrocyte count, cholesterol, total serum protein, albumin, phosphorus, and fibrinogen. At some time, the group on the moderate diet differed significantly from the deer on the high diet, with respect to hemoglobin, sialic acid, serum urea nitrogen, creatine phosphokinase, and thyroxine. Similar differences were found for animals in the wild and in enclosures. The decreased serum thyroxine in the deer on the moderate diet and in the wild deer suggests a state of hypothyroidism and decreased metabolite rate that would allow further conservation of limited energy resources but might have detrimental effects upon fetal development.

Nutritional Effects on Thyroid Activity and Blood of White-tailed Deer

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