An 8-week experiment was performed to investigate the effects of BBR on growth performance, hepatic glucose metabolism, antioxidant capacity, liver histology and intestinal digestive enzyme activity of largemouth bass. Fish (initial weight ≈122 g) were randomly allocated into 16 cages (280 L, 30 fish per tank) and fed four isonitrogenous and isolipidic diets containing 0, 0.5, 1 and 2 g/kg BBR respectively. The results indicated that diets with 1 and 2 g/kg BBR significantly promoted growth, decreased serum glucose, triglycerides (TG), total cholesterol (TC) and low-density lipoprotein cholesterol but increased serum high-density lipoprotein cholesterol (p < 0.05). The application of BBR significantly decreased hepatic alanine aminotransferase, TG and TC but increased hepatic superoxide dismutase and catalase (p < 0.05). Diets with 1 and 2 g/kg BBR significantly decreased hepatic malondialdehyde, aspartate aminotransferase and hepatic glycogen but increased intestinal farnesoid X receptor and fibroblast growth factor-19 expression and dramatically altered its downstream glycolysis- and gluconeogenesis-related genes, along with their enzyme activities (p < 0.05). Supplementation with BBR increased (p < 0.05) intestinal protease activity in B5, B10 and B20, lipase activity in B10 and B20 and amylase activity in B20. BBR reduced the liver voiding rate and fat content. These results indicated that dietary supplementation with BBR at 1 and 2 g/kg was beneficial for promoting growth and health in largemouth bass. The improved glycolysis and inhibited gluconeogenesis may account for the reduced hyperglycaemia by BBR. In addition, enhancing the activity of intestinal digestive enzymes is an effective way for BBR to improve carbohydrate utilization in largemouth bass.

中文翻译：

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BBR 对大嘴鲈鱼生长性能、血清和肝脏生化参数、肝脏形态和与糖代谢相关的基因表达水平的影响。

进行了为期 8 周的实验，以研究 BBR 对大口黑鲈生长性能、肝脏葡萄糖代谢、抗氧化能力、肝脏组织学和肠道消化酶活性的影响。鱼（初始重量≈122 g）被随机分配到 16 个网箱（280 L，每缸 30 条鱼）中，分别喂食四种含 0、0.5、1 和 2 g/kg BBR 的等氮和等脂日粮。结果表明，添加 1 和 2 g/kg BBR 的日粮显着促进了生长，降低了血清葡萄糖、甘油三酯 (TG)、总胆固醇 (TC) 和低密度脂蛋白胆固醇，但增加了血清高密度脂蛋白胆固醇 ( p < 0.05)。BBR的应用显着降低了肝脏丙氨酸氨基转移酶、TG和TC，但增加了肝脏超氧化物歧化酶和过氧化氢酶（p  < 0.05）。含 1 和 2 g/kg BBR 的饮食显着降低了肝丙二醛、天冬氨酸氨基转移酶和肝糖原，但增加了肠道法尼醇 X 受体和成纤维细胞生长因子 19 的表达，并显着改变了其下游糖酵解和糖异生相关基因及其酶活性( p  < 0.05)。补充 BBR 增加 ( p < 0.05) B5、B10 和 B20 中的肠道蛋白酶活性，B10 和 B20 中的脂肪酶活性和 B20 中的淀粉酶活性。BBR 降低了肝脏的排尿率和脂肪含量。这些结果表明，在膳食中添加 1 和 2 g/kg 的 BBR 有利于促进大口黑鲈的生长和健康。改善的糖酵解和抑制的糖异生可能是 BBR 降低高血糖的原因。此外，增强肠道消化酶活性是BBR提高大口黑鲈碳水化合物利用率的有效途径。