Oestrogen content of semen and the effect of exogenous oestradiol-17 on the oestrogen and androgen concentration in semen and blood plasma of bulls

Abstract

The concentration (mean .+-. SEM) of estrogen in semen (0.89 .+-. 0.04 ng/ml) of bulls was 8- to 9-fold higher than in blood plasma (0.10 .+-. 0.01 ng/ml), while the concentration of androgen in semen (1.15 .+-. 0.26 ng/ml) was 2.7-fold lower than in blood plasma (3.21 .+-. 0.47 ng/ml). This concentration of estrogen in semen was not influenced by 0, 1, 3 or 5 false mounts or when ejaculations occurred at 2 min intervals. When 100 mg estradiol-17.beta. was injected i.v. the estrogen level in semen followed that in the plasma.