SUMMARY

The inhibitory effect of underfeeding on the process of male pubescence was studied in three pairs of bovine identical twin calves by feeding one twin on a normal and the other on a low plane of nutrition. As a result of malnutrition the development of the androgenic function of the testes was retarded much more markedly than spermatogenesis. In the undernourished twin the testes contained and secreted less testo-sterone, and showed a lower testosterone: androstenedione ratio, than in the control animal. This nutritionally conditioned androgen deficiency was clearly reflected in a markedly retarded onset of production of fructose and citric acid by the seminal vesicles. After castration the underfed twin responded to testosterone injections much more sluggishly than the control twin, as shown by the delayed appearance of fructose and citric acid in electrically-induced ejaculates. Observations were also made on the effects of orchitis and cryptorchidism. Both these conditions lowered markedly the androgenic activity in the calves