Xie Xiaoze, Liang Xiaofang, Wang Hao, Zhu Qiang, Wang Junjun, Chang Ying, Leclercq Eric, Xue Min, Wang Jie
National Aquafeed Safety Assessment Center, Institute of Feed Research, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
Anim Nutr. 2023 Mar 7;13:302-312. doi: 10.1016/j.aninu.2023.02.011. eCollection 2023 Jun.
Cottonseed protein concentrate is a sustainable fishmeal alternative in aquafeed. A 10-week experiment was conducted to investigate the effects of a cottonseed protein concentrate-based diet with and without multi-strain yeast fractions (MsYF) on growth, bile acid metabolism, and health in largemouth bass. Four hundred fish (54.0 ± 0.0 g) were casually distributed into 16 tanks (4 replicates/diet). Fish were fed with 4 iso-nitrogen and iso-energetic diets 3 times daily, including a fishmeal diet (FM), a soy protein concentrate-based diet (SPC; replacing 81% fishmeal protein), a cottonseed protein concentrate-based diet (CPC; replacing 81% fishmeal protein), and a CPC diet supplemented with 800 mg/kg MsYF (CPCY). Results showed that the survival of SPC was the lowest, i.e., 48%, with no apparent diet effect among other treatments; we omitted the SPC in additional analyses. Fish fed cottonseed protein concentrate-based diets showed lower growth than FM ( < 0.05). Fish fed CPC showed the highest nuclear dense hepatic phenotypes ratio (50%), followed by CPCY (33%) and FM (17%). Further, dietary CPC increased hepatic total cholesterol and triglyceride levels with concurrently increased cholesterol synthesis but decreased triglyceride synthesis-associated transcription levels ( < 0.05). Furthermore, dietary CPC increased bile acid synthesis but decreased bile acid transport-associated transcription levels ( < 0.05), and then induced an increment of plasma cholic acid and hepatic chenodeoxycholic acid content and the decrement of genus ( < 0.05). Regarding the effect of MsYF, fish fed CPCY reduced hepatic lipid accumulation and total plasma bile acid content ( < 0.05) compared to CPC, suggesting an improvement in liver health. Also, dietary MsYF could reverse the microbiota community structure showing a similar gut microbial composition to FM. In conclusion, 81% of fishmeal protein replaced by cottonseed protein concentrate suppressed growth and liver health, while dietary MsYF might mitigate the negative impact of a high cottonseed protein concentrate level diet on liver functions via gut microbiota regulation.
棉籽浓缩蛋白是水产饲料中一种可持续的鱼粉替代品。进行了一项为期10周的实验，以研究基于棉籽浓缩蛋白的日粮添加和不添加多菌株酵母组分（MsYF）对大口黑鲈生长、胆汁酸代谢和健康状况的影响。400尾鱼（54.0±0.0克）被随机分配到16个水箱中（每个日粮4个重复）。每天给鱼投喂4种等氮等能量的日粮3次，包括鱼粉日粮（FM）、基于大豆浓缩蛋白的日粮（SPC；替代81%的鱼粉蛋白）、基于棉籽浓缩蛋白的日粮（CPC；替代81%的鱼粉蛋白）以及添加800毫克/千克MsYF的CPC日粮（CPCY）。结果表明，SPC组的存活率最低，即48%，其他处理组之间无明显日粮效应；在后续分析中我们省略了SPC组。投喂基于棉籽浓缩蛋白日粮的鱼生长速度低于FM组（P<0.05）。投喂CPC组的鱼核致密肝表型比例最高（50%），其次是CPCY组（33%）和FM组（17%）。此外，日粮CPC增加了肝脏总胆固醇和甘油三酯水平，同时胆固醇合成增加，但甘油三酯合成相关转录水平降低（P<0.05）。此外，日粮CPC增加了胆汁酸合成，但降低了胆汁酸转运相关转录水平（P<0.05），进而导致血浆胆酸和肝脏鹅脱氧胆酸含量增加以及属水平降低（P<0.05）。关于MsYF的作用，与CPC组相比，投喂CPCY组的鱼肝脏脂质积累和血浆总胆汁酸含量降低（P<0.05），表明肝脏健康状况有所改善。此外，日粮MsYF可以逆转微生物群落结构，使其肠道微生物组成与FM组相似。总之，用棉籽浓缩蛋白替代81%的鱼粉蛋白会抑制生长和损害肝脏健康，而日粮MsYF可能通过调节肠道微生物群减轻高棉籽浓缩蛋白水平日粮对肝功能的负面影响。
