The Adrenal Gland in White-Tailed Deer: A Significant Source of Progesterone

Abstract

The extra-ovarian contribution to peripheral blood serum progesterone levels was assessed in white-tailed deer (O. virginianus). Progesterone levels in jugular vein blood serum of adult pregnant does decreased from 7.6 .+-. 1.1 (.hivin.x .+-. SE) to 3.8 .+-. 0.4 ng/ml (P = 0.0025, 13) after pentothal anesthesia and from 10.4 .+-. 1.3 to 7.0 .+-. 1.5 ng/ml (P = 0.01, 5) after ketamine plus xylazine or promazine anesthesia. Dexamethasone reduced serum progesterone levels from 9.7 .+-. 1.5 to 6.6 .+-. 1.4 ng/ml (P < 0.001, 12). Animals receiving no treatment but sampled at the same times had similar progesterone levels (7.6 .+-. 1.5 vs. 6.1 .+-. 0.9, P > 0.9, P > 0.05, 7). ACTH elevated (P .ltoreq. 0.01) progesterone levels in fawn, adult, and gonadectomized animals of both sexes. Preliminary verification of progesterone was accomplished. These data strongly implicate the adrenal gland in deer as a significant source of progesterone and suggest that a progesterone level from a single blood sample is not reliable for assessing reproductive status.