Serum and urinary levels of reproductive hormones associated with the estrous cycle in white‐tailed deer (Odocoileus virginianus)

Concentrations of estradiol‐17β (E 2 ), progesterone (P o ), and luteinizing hormone (LH) in serum and estrone glucuronide (E 1 G) and pregnanediol glucuronide (PdG) in urine were determined by direct radioimmunoassay in five yearling and three adult female white‐tailed deer ( Odocoileus virginianus ) from 14 October to 20 December 1985. Elevated levels of LH were recorded before the first estrus of the breeding season and immediately preceding or during behavioral estrus. Urinary E 1 G and PdG concentrations were poorly correlated with serum levels of E 2 and P o , respectively. Serum P o levels prior to the first estrus of the breeding season indicate that pubertal yearlings experience silent ovulations and suggest that silent ovulations may be important in the transition from adolescence to cycling adult in white‐tailed deer.