Effects of different dietary protein‐energy ratios on growth, carcass amino acid and fatty acid profile of male and female Cherax quadricarinatus (von Martens, 1868) pre‐adults

Abstract

Cherax quadricarinatus or redclaw is considered a good option for freshwater aquaculture and has been cultivated in several countries. However, nutritional studies are scarce. In present research, the effects of different protein-energy (P/E) ratios in diets for male and female of pre-adults were investigated. Its influence on growth performance, carcass amino acid and fatty acid profiles were determined. Six different dietary P/E ratios: 12, 13, 14, 15, 16, and 17 mg of crude protein (CP) kJ−1 g−1 of food for 70 days were tested on male and female pre-adults (initial weight 10.8 ± 0.6 g). The experimental treatments were assigned in triplicate. The significantly highest (p < .05) and lower growth indices, feed utilization and survival were observed for male and female pre-adults fed a diet with a P/E ratio of 16 mg/kJ and diet with a P/E ratio of 12 mg/kJ respectively. Amino acids and fatty acids contents of the carcass on males and females (p < .05) were significantly influenced by the diets with higher P/E ratios. The two-slope broken line regression analysis and the quadratic model (second-order polynomial) regression analysis of specific growth rate in redclaw pre-adults male and female suggest that the diet containing P/E ratio of 16 mg/kJ is optimal. A diet with a dietary P:E ratio of 16 mg/kJ (240 and 80 g/kg of protein and lipid respectively) is recommended to stimulate growth performance and proper carcass amino acid and fatty acid profiles of both male and female pre-adults.