Abstract

Success has been achieved in intergeneric hybridization between two air breathing catfishes by crossing Indian catfish, Heteropneustes fossilis (Bloch) and Asian catfish, Clarias batrachus (Linn.) by in vitro fertilization technique. Four experimental trials were attempted and the highest fertilization (55.44%) and hatching (50.49%) rates were observed in the experiment IV. After 90 days of rearing, the growth rate of hybrids (65.3 ± 0.78 mm) was found to be higher than H. fossilis (55.2 ± 3.76 mm) and less than the C. batrachus (75.7 ± 0.9 mm). The survival rate of hybrids (24.75%) was observed to be less than H. fossilis (75.70%) and C. batrachus (73.13%). The karyological examination revealed that the hybrids possessed intermediate chromosomes (2n=53) between H. fossilis (2n=56) and C. batrachus (2n=50). Morphologically, the hybrids resembled one of the parent’s C. batrachus and the dorsal fin was found almost in confluent with the tail fin.

Key words: Heteropneustes fossilis, Clarias batrachus, intergeneric hybridization, chromosomes, in vitro fertilization.