Steroidal control of plasma luteiyizing hormone, comb growth and sexual behaviour in male chicks.

Abstract

Laboratoire de Biochimie et Laboratoire de Radioimmunologie, Université de Liège, 17 Place Delcour, B-4020 Liège, Belgium (Received 31 October 1977) It is well known that the concentration of luteinizing hormone (LH) in the plasma is higher in male than in female chickens (Sharp, 1975) and quail (Nicholls, Scanes & Follett, 1973), probably as a result of greater steroid feedback in the female birds (Davies, 1976). Guichard, Cédard, Mignot, Scheib & Haffen (1977) have shown that embryonic female chick gonads secrete at least ten times more oestradiol than gonads from embryonic male chicks. We have therefore investigated the relative effectiveness of androgens and oestrogens in the control of the level of LH in the male chick and whether non-aromatizable 5α-reduced androgens could depress this level, as has recently been shown in the adult quail (Massa, Davies & James, 1978). Nine groups of between three and seven 1-day-old male chicks were injected