Effect of Dietary Cholesterol on Growth Performance, Cholesterol Deposition, and Lipid Metabolism in Adult Chinese Mitten Crab (Eriocheir sinensis)

Abstract

This research investigated the effects of dietary cholesterol (CHO) on growth, molting performance, CHO deposition, and lipid metabolism of Chinese mitten crab (Eriocheir sinensis). Six diets were formulated to contain 0% (control), 0.1%, 0.2%, 0.4%, 0.8%, and 1.6% CHO and were administered to E. sinensis $\left(43.35\pm 0.05g\right)$ , for 16 weeks. From our results, crabs fed with 0.2% and 0.4% CHO diet, the final body weight (FBW), and weight gain ratio (WGR) increased significantly and the feed conversion ratio (FCR) decreased significantly compared with that of the control group. Furthermore, the molting performance of E. sinensis was significantly improved in crabs fed 0.2% CHO. Meanwhile, 0.2% CHO tends to upregulate molt-promoting genes and downregulate the expression of molt-inhibiting genes. It indicated that CHO might improve the molting performance of crabs by regulating ecdysteroid signal pathway transduction. In addition, dietary CHO can significantly increase the content of CHO in the hepatopancreas, muscle, and hemolymph. Moreover, dietary CHO increases the content of triglyceride (TG) in the hepatopancreas and hemolymph. The gene-related lipid metabolism shows that CHO may increase the lipid content by promoting lipid synthesis and inhibiting lipolysis. According to the results of this study, the dietary CHO requirement of E. sinensis is 0.27% for growth requirement and 0.45% for tissue CHO deposition based on the broken-line model.