Partial gonadectomy in the catfish Heterobranchus longifilis (Teleostei, Clariidae): Regeneration time, quality and quantity of postsurgical sperm production

Testes from adult male Heterobranchus longifilis were surgically removed, a nd the incisions sutured. Gonadectomized fish were kept in earthen ponds. T he parameters used to evaluate the efficiency of the partial gonadectomy we re the healing rate of wounds, the postsurgery survival, the time required for regeneration of the testes and the quality of postsurgical sperm produc tion. The incision closed within 7-8 weeks after surgery. The postsurgery surviva l rate was high (98%), indicating the efficiency of the surgical procedure. Functional testes were harvested 4-5 months after surgery, although the op timal regeneration time appeared to be about 6 months under the conditions prevailing in Cameroon's tropical highland climate. No significant differen ce (p >0.05) in sperm production was observed between normal and gonadectom ized fish. No difference was found in hatching rates achieved using milt de rived from regenerated testes. It is recommended that this procedure of partial gonadectomy be taken into account by hatchery managers in the design of long-term broodstock selectio n programs for catfish.