Comparative growth of reciprocal carp hybrids between Catla catla and Labeo fimbriatus

Intergeneric hybrids between catla ( Catla catla) and fimbriatus ( Labeo fimbriatus) were produced by employing the technique of hypophysation and dry stripping. Detailed investigations on their embryonic and larval development, taxonomic characters and aquaculture potential in terms of growth, feed utilization, body carcass composition, meat yield etc. were carried out. The growth experiment was conducted in concrete tanks (5 × 4 × 1.2 m) in triplicate following normal rearing practice for a period of 154 days. Growth was assessed at 14-day intervals. At the time of fish sampling, water and plankton were also analyzed. It was revealed that the growth of the hybrids was intermediate to the parental species. The final individual weights attained by catla, fimbriatus, catla X fimbriatus (male parent named first) and fimbriatus X catla were 64.2, 24.1, 39.8 and 57.8 g, respectively. Among the hybrids, the growth of fimbriatus X catla was faster than the slow-growing parent fimbriatus and the reciprocal cross hybrid and slightly less than fast-growing catla. The increase in weight attained by fimbriatus X catla was 153.4 and 45.0% more than fimbriatus and the reciprocal hybrid, respectively, but not different from catla. During the course of the investigation it was also observed that the hybrids combined desirable qualities such as the small head of the fimbriatus and the deep body of the catla and exhibited heterosis in terms of meat yield with higher flesh content than either of the parents. Hence the hybrids appear to be of considerable importance to aquaculture.