Meat Meal Replacement in Diets for Silver Perch, Bidyanus bidyanus

Abstract

Fish meal is currently the major protein source in fish feeds. However rising costs and decreasing availability of fish meal are placing pressure on the aquaculture industry to find suitable alternative sources of protein. The replacement of fish meal and fish oil in aquaculture diets may have a negative impact on the n-3 polyunsaturated fatty acid (PUFA) content of the final fish flesh. The goal of this study was to investigate the effects on production and composition especially lipid fatty acids of juvenile silver perch, Bidyanus bidyanus, by replacing dietary fish meal with meat meal. Silver perch were fed one of five diets with similar content of protein and digestible energy (DE) but different amounts of fish meal and lamb meal or ProvineR (a speciality high protein meat meal) for a period of 65 days in 10,000-L tanks. Water temperature ranged between 24.3 and 26.7°C, and aerated recirculated fresh water was filtered through a rapid rate sand filter before being supplied to experimental tanks at a flow rate of 17 L/minute. Fish growth was reduced when diets contained less than 13% fish meal and more than 9% ProvineR. No significant differences (P> 0.05) were detected in the moisture, protein, and total fat content of the silver perchfed the experimental diets. With respect to lipid composition, there were also no differences in saturated, monounsaturated, and n-6 PUFA among fish fed the experimental diets. The 27% fish meal diet produced fish with significantly (P< 0.05) higher amounts of the longer chain n-3 PUFA than fish fed the diets with meat meal. Meat meal diets produced comparable growth, similar amounts of total fat and saturated fat, but significantly lower amounts of the n-3 PUFA.