Effect of dietary protein level on the growth of Giant freshwater prawn (Macrobrachium rosenbergii) and tilapia (Oreochromis niloticus) under polyculture system in northern Bangladesh

Abstract

The present experiment was conducted to assess the effects of dietary protein on the growth of Golda (Macrobrachium rosenbergii) and Nile Tilapia (Oreochromis niloticus) in ponds for a period of 4 months under three treatments of dietary protein levels viz. T1: 20% protein level (commercial feed), T2: 25% protein level (home made feed) and T3: 30% Protein level (commercial feed) each with three replications. Prawn and tilapia were stocked @ 19760 individuals/ha and 4940 individuals/ha with mean initial stocking weight of 2.66±0.08g and 36.78±3.25g respectively. Water quality parameters (water temperature, transparency, pH, dissolved oxygen, NH3-N and alkalinity) were monitored fortnightly and growth parameters were monitored monthly. Except transparency, treatments did not vary significantly for the mean water quality parameters. Significant differences were found for the growth parameters among the treatments except the mean weight gain (monthly) and the specific growth rate (SGR). Significantly highest yield was recorded from treatment T3 where the fishes were fed with commercial feed having 30% protein level. Duncan’s multiple range test showed significantly higher (p