Effect of replacing marine protein with hydrolyzed feather meal on growth, apparent digestibility and body composition of juvenile tilapias; Oreochromis mossambicus (peters, 1852)

Abstract

The effects of substituting hydrolyzed feather meal for fresh water shrimp meal on growth, apparent digestibility and body composition in tilapia Oreochromis mossambicus were evaluated under laboratory condition. Five hundred fish were distributed in a completely randomized design with five treatments in quadruplicates with 25 fish (average weight 3.42±1.02g) per tank. The fish were fed isoproteinous (give the % protein level here) diet with increasing inclusion levels of hydrolyzed feather meal (HFM) (0%, 4%, 8%, 10% and 12%) designated as HFM0, HFM4, HFM8, HFM10 and HFM12 respectively. All the fish were fed at ad libitum for 30 days. Results indicated that fish fed the diet containing 10% inclusion level of HFM exhibited a significantly higher growth and nutritional parameters (P<0.05) in terms of mean final weight (8.05± 2.56), specific growth rate (3.67±0.29 g), food conversion ratio (1.97±0.11 g) and mean weight gain (4.9±0.33), compared to the other diets. Final body composition was influenced significantly by increasing the level of HFM through decreasing carcass moisture and lipids. Diet containing 12% HFM had significantly lower protein (11.75±0.05%) and ash (8.43±0.51) compared to diet HFM0. The study recommends at most 10% substitution of HFM for FSM for O. mossambicus culture under laboratory conditions.