Effect of different dietary protein levels on growth performance and feed utilization of hybrid catfish (Heterobranchus bidorsalis x Clarias anguillaris) fry in north-east Nigeria
The effect of different dietary protein levels on growth performance and feed utilization of hybrid catfish Heterobranchus bidorsalis (male) x Clarias anguillaris (female) larvae in north-east Nigeria were carried out in circular plastic trough (40 cm diameter x 30 cm deep) indoors. Five dietary protein levels 35, 40, 45, 50 and 55% were tried in triplicates. The result showed an increase in the growth indices with increase in dietary protein levels. Most of the growth indices mean weight gain (MWG) specific growth rate, (SGR), mean daily weight gain (MDGW), protein index (PI), apparent protein efficiency ratio (APER), food conversion ration (FCR), nitrogen metabolism (NM), relative growth rate (RGR) and percentage survival (%SR) were higher in fry fed 50% crude protein. There was no significant difference (p > 0.05) among the growth indices of fry fed on both 50 and 55% crude protein levels. Higher dietary protein level was found to give higher growth rate in this region, though expensive. The higher protein levels obtained in this study could be due to the early weaning of the hybrid larvae from shell-free artemia to compounded diet.