Abstract This study estimated the effects of different dietary carbohydrate levels on growth performance, feed utilization, body composition, and the gene expression of key enzymes involved in hepatopancreas lipogenesis and glucose metabolism in mud crab Scylla paramamosain. Crabs with an initial mean weight of 1.84 ± 0.06 g were used in an 8-week experiment to test five diets (C6, C12, C18, C24, C30) formulated to contain increasing levels of carbohydrate, measured as 8.55%, 13.36%, 17.76%, 25.64% and 32.50%, respectively. The results showed that the levels 25.64% and 32.50% improved growth performance, with the best gains at 25.64%. The highest dietary carbohydrate level led to higher hemolymph glucose concentrations and more fat deposition in the body. Furthermore, real-time quantitative PCR analysis revealed that the mRNA expression of key enzymes in glycolytic and lipogenic metabolism (i.e. glucokinase, fructose-2,6-diphosphatase, and fatty acid synthetase) were significantly affected by the dietary carbohydrate level. The mRNA expression of glucokinase was lowest in the group fed the carbohydrate-rich C30 diet, and the mRNA of fructose-2 and 6-diphosphatase were remarkably expressed in the C24 group (P

中文翻译：

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膳食碳水化合物水平对泥蟹 Scylla paramamosain 肝胰腺代谢关键酶的生长、身体成分和基因表达的影响

摘要 本研究评估了不同日粮碳水化合物水平对泥蟹生长性能、饲料利用率、身体组成以及参与肝胰腺脂肪生成和葡萄糖代谢的关键酶基因表达的影响。在为期 8 周的实验中，使用初始平均重量为 1.84 ± 0.06 克的螃蟹来测试五种饮食（C6、C12、C18、C24、C30），其配方中碳水化合物含量不断增加，测量为 8.55%、13.36%分别为 17.76%、25.64% 和 32.50%。结果表明，25.64%和32.50%的水平提高了生长性能，最佳增益为25.64%。最高的膳食碳水化合物水平导致更高的血淋巴葡萄糖浓度和更多的脂肪沉积在体内。此外，实时定量 PCR 分析显示，糖酵解和脂肪生成代谢中的关键酶（即葡萄糖激酶、果糖-2,6-二磷酸酶和脂肪酸合成酶）的 mRNA 表达受膳食碳水化合物水平的显着影响。葡萄糖激酶mRNA在富含碳水化合物的C30组中表达最低，果糖2和6-二磷酸酶mRNA在C24组中显着表达（P