Concerning the effect of prostate feeding on tadpoles

Abstract

Gudernatsch was the first to call attention to the remarkable influence of the feeding of thyroid and thymus glands on frogs'rarvæ. That observer noted that the thyroid causes a dwarfing or shrinkage of the growth and size of tadpoles, and at the same time very rapidly hastens their metamorphosis into frogs, while the thymus, on the other hand, causes giant tadpoles but inhibits their metamorphosis. Gudernatsch and other observers have also studied the effect of feeding of other organs and glands on the development of frogs'rarvæ. As far as the present author has been able to ascertain, however, no experiments concerning the feeding of prostate gland to tadpoles are on record. The present author, in connection with a physiological and pharmacological study of prostatic extracts, conducted a series of experiments in feeding tadpoles with desiccated prostatic substance (Armour). The results are so interesting that it is deemed desirable to make a preliminary announcement on the subject in this place.

Prostate gland was fed to tadpoles of several species of frogs and it was noted that like the thyroid, the feeding of prostate substance tended to hasten the transformation of the larvæ into frogs. Such an effect was occasionally noted after administration of the gland substance for three or four days, and generally was distinctly noticeable after a period of from ten to fourteen days.

Unlike the effects of thyroid feeding, the feeding of prostatic substance while hastening metamorphosis did not produce much shrinkage in the size of the tadpoles. Indeed, it very often seemed to promote the growth of the tadpoles to a greater degree than was noted in the control animals. It was further noted, that prostatic substance was very much less toxic to the larvae than was thyroid substance, so that the tadpoles could be fed on the prostate continuously without being killed.