Effects of dietary cholesterol levels on moulting performance, lipid accumulation, ecdysteroid concentration and immune enzymes activities of juvenile Chinese mitten crabEriocheir sinensis

Abstract

Effects of dietary cholesterol levels on moulting performance, lipid accumulation, ecdysteroid concentration and immune enzymes activities of juvenile Eriocheir sinensis were investigated. Crabs were fed with feeds contained various cholesterols of 1100, 2100 and 3200 mg kg À1 in both paddy fields and laboratory experiments. In paddy fields trial, the crabs fed with diets contained 3200 mg kg À1 cholesterol achieved higher growth rate than those fed with diets contained no supplemental cholesterol (1100 mg kg À1 ). In laboratory trial, moulting frequencies of crabs fed with diets contained 3200 mg kg À1 cholesterol were higher than those of crabs fed with diets contained no supplemental cholesterol from the 6th to 10th moult. Further laboratory experiment indicated that intermoults of crabs fed with diets contained 3200 mg kg À1 cholesterol significantly shortened compared with crabs fed with the basal feeds (1100 mg kg À1 cholesterol). In the intermoult, total lipid content, ecdysterone concentration and three immune enzymes in crabs were increased with the increment of dietary cholesterol levels between the 7th and the 8th moult in laboratory experiments. Taken together, dietary cholesterol not only enhanced moulting performances of growth, survival and moult frequency, but also enhanced total lipid storage, ecdysterone concentration and three immune enzymes activities in the intermoult period.

Effects of Dietary Cholesterol Levels on the Growth, Molt Performance, and Immunity of Juvenile Swimming Crab, Portunus trituberculatus

“…This suggests that cholesterol supplementation improves the immune response of swimming crabs. Similar results were also observed in Eriocheir sinensis (Tao et al, 2014) and Oncorhynchus mykiss (Deng et al, 2013). However, the ACP and AKP levels of swimming crabs fed diet with 1.4% cholesterol were lower than those fed diets with 1.0% cholesterol.…”

“…It is well known that crustaceans are incapable of de novo synthesis of sterols and require an exogenous dietary source of cholesterol for growth, development, and survival. Cholesterol is the ultimate precursor for the synthesis of ecdysone, which is closely involved in the process of molting in crustaceans (Sheen, 2000;Tao et al, 2014). Moreover, cholesterol is a precursor of vitamin D, which enhances the immune system (Tao et al, 2014).…”

Dietary protease modulates nutrient retention efficiency and hepatopancreatic protease activity in juvenile Chinese mitten crab Eriocheir sinensis

“…In 2014, the total commercial production of Chinese mitten crab has reached at about 800,000 MT/year exceeding 5.5 billion USD in value (FAO ; Yuan, Wang, Zhang, Li, & Liu, ). Because of their high value, the species has been receiving significant attention to investigate various aspects of physiology and genetics (He et al., ), nutritional requirement (Pan, Xiao, Zhang, & Luan, ), digestible protein‐to‐energy ratio (DP:DE) (Cui et al., ; Li, Li, Liu, & Murphy, ), water temperature (Yuan et al., ) and the effects of various macro‐ and micronutrients such as phospholipid, cholesterol, vitamins and long‐chain fatty acids on production performance (Sui, Wille, Cheng, & Sorgeloos, ; Sun, Chen, Chen, Jiang, & Li, ; Sun et al., ; Tao et al., ; Wang et al., ; Wei et al., ; Wu et al., ). Recently, there is some focus on disease and immune enhancement of the species under farmed conditions (Ding et al., ; Wang et al., ).…”

Effects of Dietary Phospholipid and Cholesterol Levels on Growth, Molting Performance, and Ovary Development in Female Juvenile Crayfish (Procambarus clarkii)

“…The underlying reasons for molt death syndrome are related to inadequate content of nutrients (e.g., high unsaturated fatty acids, PL, CH, and total lipids), which are stored in the hepatopancreas [11,[28][29][30]. Previous studies have shown that CH transported from the hepatopancreas results in the variation of the ecdysteroid signal transduction and changes the molting performance in crustacean [4,31,32].…”