Preparation and utilization of fish waste protein concentrate in diets for young common carp, Cyprinus carpio L.

This research was carried out to investigate the extraction of a protein concentrate from the viscera of the common carp, Cyprinus carpio L. to use as a partial substitute for fish meal in the diets of young common carp and to test its effect on growth indices and feeding efficiency. Two methods were adopted to extract the protein concentrate; physical method and chemical. Proximate composition of raw fish wastes, fish protein concentrates and different experimental feeds were analysed and several parameters of fish feeding and growth efficiency of cultured fish were studied. Fish were fed with a formulated diet for 60 days. The protein concentrate extracted by physical method was selected to prepare experimental diets for its higher yield. Four diets with substitution ratios of 0, 25%, 50% and 75% of fish meal were prepared. The results showed significant differences (p 0.05) between the experimental feeds as to total weight gain rates, specific growth rate (SGR), food conversion ratio (FCR), protein efficiency ratio (PER) and protein productive value (PPV). The study concluded the possibility of partial replacement of fish meal up to 50% in the diets of young common carp without any significant deleterious influence on feeding and growth indices or noticeable adverse effect on cultured fish.