Reproductive characteristics and larval development from different broodstoock sources of bighead catfish(Clarias macrocephalus)

Abstract

Bighead catfish, Clarias macrocephalus, is an important species for aquaculture. Nevertheless, there are few studies about population-variation in their reproductive characteristics and larval growth. This research was aimed to evaluate reproductive performance and larval development of three bighead catfish broodstock sources. Broodstock were collected from two wild populations in Ca Mau (CM) and Hau Giang (HG) provinces, and one domesticated population in Can Tho (CT). Three groups of fish were cultured under optimal maturation conditions in a recirculating aquaculture system for three months. Then, 16-18 pairs from each broodstock source were artificially propagated. Their reproductive performance (i.e., relative fecundity, fertilization rate, hatching rate, deformity rate, and egg diameter) and larval development (including parameters of york sac and body length after hatch, survival and growth rates) were compared among three broodstock sources.Results indicated that three broodstock sources showed difference reproductive performance in terms of relative fecundity, fertilization rate, hatching rate,. In which the Can Tho domesticated strain was highest and wild fish in Ca Mau was lowest. Furthermore, reproductive traits including fertilization rate and hatching rate were quite high in all groups, and newly hatched larvae and yolk sac volume were higher in wild groups ( Ca Mau and Hau Giang) compared to cultured Can Tho fish. Overall, difference broodstock sources did not affect significantly on larval growth and survival rate.