SUMMARY

The androgenic effects of testosterone and dihydrotestosterone on the bovine seminal vesicles have been evaluated by (i) introducing the steroid directly into one seminal vesicle in situ, while retaining the other vesicle as a control or for the introduction of another steroid, or (ii) injecting the steroid subcutaneously into a whole animal, and examining the seminal vesicles after autopsy. When introduced directly into a seminal vesicle dihydrotestosterone oenanthate stimulated growth and the formation of fructose and citric acid, but the magnitude of the effect was not greater than that of a similar dose of testosterone oenanthate. When twin calves were injected subcutaneously, one with dihydrotesto-sterone propionate, and the other with the same dose of testosterone propionate, only the latter responded with increased output of fructose, citric acid and \g=a\-mannosidasein electro-ejaculated semen. But the seminal vesicles grew to approximately the same size in both twins. Parenterally administered bovine growth hormone produced a sudden but transient burst of secretory activity in the seminal vesicles, resulting in the appearance of fructose and citric acid in electro-ejaculated semen