The secretory characteristics of GTH and sexual hormone of Jining gray goat during the oestrus cycle.

The jugular vein blood samples of Jining Gray She-Goat were collected during the oestrus cycle.The secretory characteristics of FSH,LH,E2 and P were measured using radioimmunoassay system(RIA).The four secretory peaks of FSH,LH and E2 was found during the oestrus cycle.The secretory peaks of FSH were later than that of LH.The secretory peaks of E2 appeared with LH at the same time except the 3rd secretory peaks.The P increased gradually from the 5th day and maintained the high concentration in the anoestrus(P0.05),then decreased rapidly in the 18th.The secretion of FSH and LH was pulsatile during the oestrus and anoestrus and the Estrogens and Progesterone was wavelike.Furthermore,the pulse frequency of FSH during the oestrus was lower than the anoestrus(P0.05).the contrary,the pulse frequency of LH during the anestrous was higher than the anoestrus(P0.05).