Chen Fang, Ding Zhirong, Su Zeliang, Guan Junfeng, Xu Chao, Wang Shuqi, Li Yuanyou, Xie Dizhi
College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China.
Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China.
Animals (Basel). 2024 Jul 28;14(15):2196. doi: 10.3390/ani14152196.
Inappropriate substitution of dietary fishmeal (FM) can adversely affect the growth, health, and metabolism of carnivorous fish species. To effectively reduce the amount of dietary FM in carnivorous largemouth bass (), a terrestrial compound protein (Cpro) with chicken meal, bone meal, and black soldier fly protein was used to formulate four isoproteic (52%) and isolipidic (12%) diets, namely T1 (36% FM), T2 (30% FM), T3 (24% FM), and T4 (18% FM), for feeding juveniles (initial weight: ~12 g) for 81 days. Results indicated that the growth performance, feed efficiency, and morphological indicators, as well as muscle texture and edible quality of fish, did not differ significantly among the four groups. However, the muscle protein contents and ATP/AMP ratio of fish in the T4 group were significantly increased in comparison with those of fish in the T1 group, while the opposite was true for muscle glycogen. Compared with the T1 group, high serum total amino acid and MDA contents, as well as low AST activities, were observed in the T3 and T4 groups, and relatively high intestinal trypsin and lipase activities were found in the T2-T4 groups. The transcripts of intestinal proinflammatory cytokines (, , and ) were downregulated in the T2-T4 groups compared with T1 group, while the expression of anti-inflammatory cytokines () and tight junction ( and ) showed the reverse trend. The mRNA expression of positive regulators related to protein synthesis (, , , and ) were significantly upregulated in the muscle of fish fed diets T3 and T4, while their negative regulators () mRNA levels were downregulated. The results indicate that the dietary FM of largemouth bass could be effectively reduced to at least 18% by the Cpro, which is beneficial to health, digestion, and protein synthesis for maintaining accelerated growth.
不恰当替代饲料中的鱼粉（FM）会对肉食性鱼类的生长、健康和新陈代谢产生不利影响。为有效减少肉食性大口黑鲈饲料中的鱼粉用量，使用一种包含鸡肉粉、骨粉和黑水虻蛋白的陆生复合蛋白（Cpro）配制了四种等蛋白（52%）和等脂（12%）的饲料，即T1（36%鱼粉）、T2（30%鱼粉）、T3（24%鱼粉）和T4（18%鱼粉），用于投喂幼鱼（初始体重：约12克）81天。结果表明，四组之间鱼的生长性能、饲料效率、形态指标以及肌肉质地和食用品质均无显著差异。然而，与T1组相比，T4组鱼的肌肉蛋白质含量和ATP/AMP比值显著增加，而肌肉糖原则相反。与T1组相比，T3和T4组血清总氨基酸和丙二醛含量较高，天冬氨酸转氨酶活性较低，且T2 - T4组肠道胰蛋白酶和脂肪酶活性相对较高。与T1组相比，T2 - T4组肠道促炎细胞因子（、和）的转录本下调，而抗炎细胞因子（）和紧密连接（和）的表达则呈相反趋势。在投喂T3和T4饲料的鱼肌肉中，与蛋白质合成相关的正调控因子（、、、和）的mRNA表达显著上调，而其负调控因子（）的mRNA水平下调。结果表明，复合蛋白可将大口黑鲈饲料中的鱼粉有效减少至至少18%，这有利于健康、消化和蛋白质合成，以维持快速生长。
