Chicken meal, shrimp meal, blood meal, and soybean protein concentrate are common alternatives to fishmeal. This study used them to prepare three diets with different levels of fishmeal (FM48, FM40, and FM32) for largemouth bass (Micropterus salmoides). The results found no significant difference in the growth performance of largemouth bass fed different diets. Mixed protein increased the total cholesterol (T-CHO) content in plasma, and reduced the total superoxide dismutase (T-SOD) activity in plasma and liver. Targeted metabolomics analysis found that the low fishmeal diets affected the cholesterol and bile acid metabolism of largemouth bass. Mixed protein inhibited cyp7a1 and enhanced hmgcr and pparγ mRNA levels, as well as enhanced the expression levels of FXR in the liver. The fish-fed FM32 diet showed inhibited fxr, rxrα, and cyp7a1 mRNA levels in the intestine. The results of TUNEL fluorescence staining showed that mixed protein induced apoptosis in largemouth bass. The caspase 3 and caspase 9 mRNA levels in the fish-fed FM40 and FM32 diet significantly increased, as well as the expression levels of CASPASE 3. The experiment also found that it could induce oxidative stress and endoplasmic reticulum stress. In conclusion, the replacement of fishmeal with mixed animal and plant protein diets did not affect the growth performance, but the health and bile acid metabolism of largemouth bass was affected when the fishmeal level was reduced to 32%.

中文翻译：

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替代鱼粉的动植物混合蛋白来源影响大口黑鲈 （Micropterus salmoides） 的胆汁酸代谢和细胞凋亡


鸡粉、虾粉、血粉和大豆浓缩蛋白是鱼粉的常见替代品。这项研究用它们为大口黑鲈 （Micropterus salmoides） 准备了三种具有不同鱼粉含量（FM48、FM40 和 FM32）的饮食。结果发现，饲喂不同日粮的大口黑鲈的生长性能无显著差异。混合蛋白增加了血浆中的总胆固醇 （T-CHO） 含量，并降低了血浆和肝脏中的总超氧化物歧化酶 （T-SOD） 活性。靶向代谢组学分析发现，低鱼粉饮食影响了大口鲈鱼的胆固醇和胆汁酸代谢。混合蛋白抑制 cyp7a1 并增强 hmgcr 和 pparγ mRNA 水平，以及增强肝脏中 FXR 的表达水平。鱼饲 FM32 饮食显示肠道中的 fxr 、 rxrα 和 cyp7a1 mRNA 水平受到抑制。TUNEL 荧光染色结果显示，混合蛋白诱导大口黑鲈细胞凋亡。鱼饲 FM40 和 FM32 日粮中 caspase 3 和 caspase 9 mRNA 水平显著升高，CASPASE 3 表达水平也显著升高。实验还发现，它可以诱导氧化应激和内质网应激。综上所述，动植物蛋白混合饲料替代鱼粉对生长性能没有影响，但当鱼粉水平降低到32%时，影响了大口黑鲈的健康和胆汁酸代谢。