Growth Performance of Strain-Crossed Hybrid of Rohu (Labeo rohita) Among Two Rivers & a Hatchery

Abstract

Two of the approaches for improvement of growth performance in the aquaculture species are selection and hybridization. Depending upon breeding cycle of a species, selection program can always be time consuming; however, hybridization that exploits dominant genetic variation (Vᴅ), production of F₁ hybrids is quicker and although nicking of dominant allelic action in hybrids is fortuitous, the program is worth trying. With this aim in view, six reciprocal hybrid crosses were made between three strains of rohu (Labeo rohita) from the Padma, Halda and from a local Hatchery from Jessore, Bangladesh, together with control crosses of the three single strains. The participating broods were tagged intraperitoneally with digital tags and preserved in the pond facility of Bangladesh Fisheries Research Institute, Jessore campus. The fishes of the different crosses were tested for length and weight for 18 weeks in ponds. The single strain, Padma × Padma showed the highest growth performance followed by one of the reciprocal crosses between Hatchery ♂ × Padma ♀. The lowest growth performance was observed in the single strain Hatchery × Hatchery crosses which were deemed obvious as poor performance of hatchery produced seed is variously claimed by the farmers. Hybrid seed production is an established method in agriculture, in general. Thus the parents of strain crossed foregoing hybrid which were conserved with tag marks in Jessore campus of BFRI can be used for hybrid seed production in future.