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

Abstract

The concentration (mean ± S.E.M.) of oestrogen in semen (0.89 ± 0.04 ng/ml) of bulls was 8.9 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 oestrogen in semen was not influenced by 0, 1, 3 or 5 false mounts or when ejacuations occurred at 2-min intervals. When 100 mg oestradiol-71β were injected i.v. the oestrogen level in semen followed that in plasma.