THE DEVELOPMENT OF SECONDARY SEX CHARACTERS IN CAPONS BY INJECTIONS OF EXTRACTS OF BULL TESTES

Abstract

The authors describe studies of an extract of bull testes which, when injected, hypodermically or intramuscularly, into brown leghorn capons causes growth of the comb, wattles, and ear lobes. The material is a benzene soluble lipin fraction of an alcoholic extract of finely ground testes, previously described in 1927. Some chemical and physical properties of the crude preparation together with its effect upon the castrated brown leghorns are given. The amount of lipin material injected daily for maximum comb growth in one capon represents from 150 to 200 gm. of fresh testicle tissue. The crude lipin found in the benzene soluble fraction can be freed somewhat from non-potent material by fractional precipitation by methyl alcohol, ethyl alcohol, and acetone, or by extraction by liquid ammonia. Although the reactivity of the individual capons varies, these variations are of such a nature that this biological reaction can be used as a rough quantitative method for assaying such lipin preparations. Very frequently serious local reactions appear at the site of injection and much unabsorbed material may remain. The preparation when injected into bilaterally castrated hens induces good comb growth.