Effect of Desiccated Beef Testis Upon Sex Glands of the Rat

The prostate gland of the rat shows a marked increase in weight in aged males. 1 McGee 2 and Gallagher and Koch 3 have shown that the testicular hormone of the beef testis is lipoid soluble. Moore and McGee 4 state that the lipoid fraction of the beef testis possesses the same activity as the internal secretion of the testis, judged by its effect on spermatozoa in isolated epididymes. We have fed beef testis to mature male rats in an attempt to determine whether it might have any effect on the increase in weight of the prostate gland, as it tends to occur in the aging animals. The testes were ground and desiccated at 65°C., without removal of fat or extractives. The desiccated testis was then refrigerated and fed in 0.2 gm. amounts, 5 times a week. The experimental animals gave no visible evidence of departure from the condition of litter-mate controls. When sacrificed however, the testes, prostate gland and seminal vesicles were found to be considerably smaller than in the control animals. There was no contrast in the weights or gross appearance of the livers and spleens in the 2 groups. Table I presents the weights of the control rats together with the weights of their testes with epididymes, prostate glands and seminal vesicles. The average weights of these organs are given and the fractional proportion of the average total body weight represented by each organ is stated. Table II presents the same figures for the experimental animals, together with the number of doses of desiccated testis received by each and the period over which the feeding extended. It will be noticed that the weight of the sex glands is considerably less in the experimental animals than in the controls.