This study investigated the effects of different combinations of protein and carbohydrates on growth performance, body composition, blood and liver biochemical parameters, and intestinal enzyme activities of Rhamdia quelen. The jundiá (4.03 ± 0.02 g) were divided into groups with each group fed for 40 days with a diet as follows: casein + corn starch (CASCS), casein + fructose (CASFRU), gelatin + casein + maltodextrin (GCASMALDEX), fish meal + corn starch (FMCS), and fish meal + fructose (FMFRU). After this period, significantly higher growth was observed in fish that were fed the FMCS diet. In addition, the fish in the FMCS treatment group exhibited higher levels of amino acids, cholesterol, glucose, and plasma proteins, higher activity of lipase and lower activity of chymotrypsin and trypsin, and higher protein and lipid retention than those in other treatments. The digestive somatic index of the fish on the CASFRU diet increased significantly throughout the experimental period. Increased activity of maltase in the jundiá that received the CASCS diet, and alanine aminotransferase in the fish receiving the FMFRU treatment were observed. In conclusion, the jundiá that received the FMCS diet showed better digestive and metabolic efficiency and consequently better growth performance.

中文翻译：

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同步使用蛋白质和碳水化合物来源以提高容迪亚的生长性能

本研究调查了蛋白质和碳水化合物的不同组合对鼠尾草生长性能、身体成分、血液和肝脏生化参数以及肠道酶活性的影响。. 将 jundiá (4.03 ± 0.02 g) 分成几组，每组饲喂 40 天，其饮食如下：酪蛋白 + 玉米淀粉 (CASCS)、酪蛋白 + 果糖 (CASFRU)、明胶 + 酪蛋白 + 麦芽糊精 (GCASMALDEX)、鱼鱼粉 + 玉米淀粉 (FMCS) 和鱼粉 + 果糖 (FMFRU)。在此之后，在喂食 FMCS 饮食的鱼中观察到显着更高的生长。此外，FMCS处理组鱼的氨基酸、胆固醇、葡萄糖和血浆蛋白水平较高，脂肪酶活性较高，糜蛋白酶和胰蛋白酶活性较低，蛋白质和脂质滞留率高于其他处理。在整个实验期间，CASFRU 饮食中鱼的消化体细胞指数显着增加。接受 CASCS 饮食的 jundiá 中麦芽糖酶的活性增加，观察到接受 FMFRU 处理的鱼中的丙氨酸氨基转移酶。总之，接受 FMCS 饮食的 jundiá 显示出更好的消化和代谢效率，从而更好地生长性能。