Effect of the dopamine antagonist, domperidone alone and in combination with thyroxine, clomiphene, hcg or gnRH on serum sex steroid profile, gonadal maturation and spawning of nile catfish, clarias lazera

ABSTRACT

The present investigation was carried out on one hundred and twenty mature Clarias lazera fish during the prespawning season [March - April]. Fish were allocated into two main groups [sixty fish of each sex] Fish weight ranged between 200-220 g. b. wt. Each main group was subdivided into six equal groups [Ten fish each], Fish of each group; both males and females were subjected to the same regimen of intraperitoneal exogenous treatment, as follows. 1[st] Group Saline 0.65% NaCL solution. [Control] 2[nd] Group Domperidone 5 microg/g. b. wt. in saline. 3[rd] Group Domperidone 5 microg/g. b. wt, plus thyroxine 1 nancg / g. b. wt. in saline. 4[th] Group; Domperidone 5 microg/g, b. wt. plus clomiphene citrate l gamma g/g. b wt. in saline. 5[th] Group Domperidone 5 micro g/g. b. wt. plus hCG 2 lU/g, b. wt. in saline. 6[th] Group Domperidone 5 microg/g. b. wt. plus GnRH 10 microg/kg. b. wt. in saline. The present study revealed that [Domperidone] administration alone, in each sex of Clarias fish; increased serum sex steroid hormones [testosterone and 17 beta estradiol], gonadal weights [testes and ovaries], final gonadal maturation and gonadosomatic indices of both sexes as compared to respective controls. Exogenous administration of domperidone plus gonadotropin releasing hormone [GnRH] was the most effective treatment for production of sex hormones, final gonadal maturation and spawning in both sexes of Clarias lazera fish, followed by domperidone plus thyroxine; domperidone plus clomiphene citrate and domperidone plus hCG, respectively. In conclusion, the exogenous administration of dopamine antagonist plus GnRH is the most efficient regimen for enhancement of gonads maturation [gonadal recrudescence], spawning and spermiation of Clarias lazera fish throughout the prespawning season