Growth Performance and Nutrient Utilizations of Heterobranchus bidorsalis (Geoffory Saint Hilaire, 1809) Fed on Fermented Sorghum Bran Meal Diets

Abstract

The growth of aquaculture faces a high cost of feed which is about 60% to 75% of total production costs. An effort should be made to increase the profit by reducing the cost of feed as minimal as possible. This study investigated the growth performance and nutrient utilizations of Heterobranchus bidorsalis fed on fermented sorghum bran meal diets. sorghum bran was fermented at 10% moisture for seven days and samples for proximate analysis were collected on the first, fourth and seventh day. The highest crude protein was obtained in seventh day fermentation with 17.59±1.53% and the lowest was obtained in the zero day (control) with 10.53±1.53. Four isoproteic diets (40% crude protein) were formulated at 25%, 50%, 75% and 100% inclusion level to replace maize meal. The diets were fed to H.bidorsalis for twelve weeks. The experimental fish were fed 5% body weight throughout the experiment. The results obtained from the feeding trial showed that the fish fed on 100% inclusion level shows significance difference (p<0.05) in mean weight gain compared to fish fed on other diets. The highest mean weight gain (MWG) was obtained in the fish fed on 100% inclusion level diet (D5) with 43.39±1.86g and the lowest was obtained in control diet (D1) with 28.97±0.54g. The highest Average Daily Growth (ADG) and Specific Growth Rate (SGR) were obtained in the fish fed on (D5) with 0.52±0.56 and 1.07±0.64 while the lowest were obtained in the fish fed on control diet with 0.35±0.51 and 0.91±0.65 respectively. The nutrient utilizations showed significant difference (p<0.05) in fish fed on (D5) compared to others. The highest feed conversion ratio (FCR) was obtained in fish fed on (D5) with 0.48±0.16 and the lowest was obtained in control with 0.41±0.24. The highest protein intake (PI), protein rating (PR) and protein growth rate (PGR) were obtained in the fish fed on (D5) with 43.12±1.27, 0.52±0.72 and 1.04±0.71 while the lowest were obtained in the fish fed on control with 29.99±0.71, 0.35±0.45 and 1.00±0.53 respectively. The highest Protein Efficiency Ratio (PER) was obtained in the fish fed on (D5) with 1.01±0.07 and the lowest was obtained in the fish fed 50% inclusion level diet (D3) with 0.95±0.62. The highest Apparent Net Protein Utilization (ANPU) and Apparent Net Lipid Utilization (ANLU) were recorded in the fish fed on (D5) with 23.35±0.92 and 161.22±0.26 while the lowest were recorded in the fish fed on (D1) with 14.68±1.05 and 131.27±0.74 respectively. This study revealed the positive effects of incorporating fermented Sorghum bran meal into the diet of H. bidorsalis.