Correlation of the drug combination to the spawning and the sex steroid hormone secretion in fish

The changes occurring in the loach sex steroid hormones in the blood and the egg were observed.The analogues of the gonadotropin releasing hormone(GnRH) [desGly10(D-Leu6,Trp7,Leu8) GnRH],the dopaminergic receptor antagonists,and the selective estrogen receptor modulators were investigated by the radioimmune assay.The endogenous hormone changes caused by different drug combinations and the correlation of the changes to the ovulation were evaluated by the dependablity analysis.The comparative study was made on the systemic content changes in the endogenous hormone caused by the different drug combinations and on the endogenous hormone contents at the different sampling times so as to explore the correlation of the exogenous drug combination to the effect of the fish artificial propagation and to find out the highly-proficient oxytocic for the fish breeding.An increasing tendency of the correlation was found between the different GnRH levels and the fish ovulating arrival in the pregnant loach(Paramisgurnus dabryanus).The levels of estradiol(E2) and testosterone(T) in the blood serum and the progesterone (P) in the egg white had an increasing tendency,which demonstrated that a strong correlation existed between the drug combination and the fish ovulating effect.The synergism changes in the levels of the gonadal steroid hormones in the blood and the egg white could be used as an important biological identification marker in the fish ovulation assessment,and the changes had the pharmacodynamic effects.