Body weight at harvest and its heritability estimate in Clarias magur (Hamilton, 1822) reared under mono and polyculture systems

Abstract

The present study was aimed to identify the effect of non-genetic factors on harvest body weight of Clarias magur (Hamilton, 1822) reared under mono and polyculture systems and to estimate its heritability. Magur fishes from three different geographical regions viz., Andhra Pradesh, Assam and West Bengal were procured and stocked at Fresh Water Fish Farm (FWFF) of ICAR-Central Institute of Fisheries Education, Balbhadarpuram, Kakinada, Andhra Pradesh, India. A total of 139 pairs of fishes were mated to produce full-sib families of which only 42 families had either 15 or more offsprings or survived till tagging and of these a total of 1373 fishes were PIT (Passive Integrated Transponder) tagged. Tagged fishes were reared in mono and polyculture systems. In polyculture system, magur were stocked along with rohu Lobeo rohita fishes. The average harvest body weight of magur reared in monoculture was 146.27±1.36 g and was significantly higher than the average body weight of fishes reared in polyculture (137.33±2.28 g) (p<0.05). Male fishes were significantly heavier than females at harvest. The heritability for harvest body weight from animal model was 0.55±0.76 and from single pair mating it was 0.63±0.10. The heritability for harvest body weight in mono and polyculture systems differed from one another.