Impacts of different feeding modes on the gonadal development, total edible yield, and nutritional composition of male Chinese mitten crab (Eriocheir sinensis)

Abstract

This study analyzed the tissue indices, proximate composition, fatty acid and amino acid composition of edible tissues of male E. sinensis under three feeding modes (formulated diets (FD), natural diets (ND), and traditional diets (TD)). The results showed that different feeding modes had no impacts on the overall gonadal development, as no significant difference was found in gonadsomatic index among three treatments. For edible yield, three modes all had similar levels of the meat yield, hepatosomatic index, and total edible yield. Although different feeding modes did not affect the individual edible yield and gonadal development, significant differences were detected in the nutritional composition of males from three modes. For proximate composition, significant differences were found in the total lipids of gonads and the carbohydrate of hepatopancreas and meat. For fatty acids, crabs from ND had a higher proportion of monounsaturated fatty acids. In gonads and hepatopancreas, FD had a higher proportion of long-chain polyunsaturated fatty acids. For amino acids, FD had higher amino acid contents, while ND had the lowest. Except tryptophan, the essential amino acids scores of the meat were all greater than 100. As there was no significant difference on meat quality and meat yields between three feeding modes, this study suggests that the formulated diet could replace the natural diet and traditional diet towards sustainable crab farming in future.