Egyptian Journal of Aquatic Research (Sep 2019)
Growth performance and carcass quality of river catfish Hemibagrus nemurus fed salted trash fish meal
Abstract
The objective of the study was to examine the substitution effect of fish meal by salted trash fish meal in the diet on the growth performance and carcass quality of river catfish Hemibagrus nemurus. Four diets (34% protein and 3.25 kcal g-1 digestible energy) were tested; the control diet contained fish meal without salted trash fish meal (FM), and the other diets were salted trash fish meal diets with fish meal, which was reduced and proportionally replaced by salted trash fish meal 50% (STFM-50), 75% (STFM-75), 100% (STFM-100); and a commercial diet (CD), containing 31.79% protein and 2.94 kcal digestible energy, was used as a reference diet. The juvenile catfishes (with average in body weight 50 ± 2.26 g) were stocked into 2 m × 2 m × 1.20 m floating net cages at a density of 50 fish cage−1, and fed experimental diets at satiation, twice a day at 7.00 AM and 17.00 PM for 12 weeks. The results showed that the substitution of fish meal by salted trash fish meal up to 75% did not give significant effect on pelleted diet water stability, growth performance (survival rate, weight gain, specific growth rate, feed efficiency, protein efficiency) and carcass quality (body proximate composition, amino acid profile, edible flesh, dress-out percentage, carcass waste and sensory quality) of the fish (P > 0.05). However, complete substitution (100%) reduced protein retention and fish body protein (P < 0.05). Compared to commercial diet, the substitution of fish meal by salted trash fish meal up to 75% produced higher protein retention, fish body protein and sensory quality of the fish (P < 0.05). Therefore, it is concluded that the salted trash fish meal can be included in the diet of river catfish H. nemurus up to 75%. Keywords: Salted trash fish, Fish meal, Feed utilization, Growth performance, Carcass quality