Chen Chengzhuang, Xu Chang, Yang Xiaolong, Jia Yongyi, Gu Zhimin, Li Erchao
Key Laboratory of Tropical Hydrobiology and Biotechnology of Hainan Province, Hainan Aquaculture Breeding Engineering Research Center, College of Marine Sciences, Hainan University, Haikou, Hainan 570228, China.
Agriculture Ministry Key Laboratory of Healthy Freshwater Aquaculture, Key Laboratory of Fish Health and Nutrition of Zhejiang Province, Key Laboratory of Freshwater Aquaculture Genetic and Breeding of Zhejiang Province, Zhejiang Institute of Freshwater Fisheries, Huzhou 313001, China.
Aquac Nutr. 2022 Sep 20;2022:2640479. doi: 10.1155/2022/2640479. eCollection 2022.
As a new species in aquaculture, the lipid nutrition requirement for the juvenile redclaw crayfish on a dietary basis on a practical formula needs to be evaluated accurately. In this study, the optimum dietary lipid level was explained by analyzing the growth performance, antioxidant state, lipid metabolism, and gut microbiota of after an eight-week cultivation trial. Six diets with different soybean oil levels (named L0, L2, L4, L6, L8, and L10) were fed to (11.39 ± 0.28 g). The results indicated that the specific growth rate and weight gain of crayfish fed the L4 and L6 diets were significantly higher than those of the other groups ( < 0.05). By the analysis of a second-order polynomial regression model according to growth performance (weight gain rate), the optimum lipid level in a practical diet for juvenile was 9.67%. The survival, condition factor, and hepatosomatic index of crayfish were not significantly affected by dietary oil levels ( > 0.05). As the level of dietary lipids increased, the total antioxidant capacity and glutathione peroxidase activity in serum showed a tendency to rise and then fall and the enzyme activity was highest in crayfish fed the L6 diet. Gut lipase and pepsin activities showed the highest value in crayfish fed the L6 diet. There was no significant difference in acetyl-CoA carboxylase and carnitine palmitoyltransferase-1 contents in crayfish among all the groups ( > 0.05). The relative abundance of in the phylum and in the genus showed a significant decrease in crayfish of the L10 diet, while the relative abundance of in the phylum markedly increased compared to that of the other groups ( < 0.05). In summary, the results indicated that the 10.39% (L6 diet) dietary lipid level could induce better growth performance, antioxidant ability, and digestive enzyme activity. Most of the fatty acid composition of muscle is not closely related to the fatty acid composition of the diet. Moreover, the composition and diversity of the gut microbiota of were changed by high dietary lipid levels.
作为水产养殖中的一个新物种，需要准确评估基于实用配方饲料的幼体红螯螯虾的脂质营养需求。在本研究中，通过对八周养殖试验后的生长性能、抗氧化状态、脂质代谢和肠道微生物群进行分析，阐述了最佳饲料脂质水平。将六种不同大豆油水平的饲料（命名为L0、L2、L4、L6、L8和L10）投喂给体重为（11.39±0.28克）的红螯螯虾。结果表明，投喂L4和L6饲料的小龙虾的特定生长率和增重显著高于其他组（P<0.05）。根据生长性能（增重率）通过二阶多项式回归模型分析，幼体红螯螯虾实用饲料中的最佳脂质水平为9.67%。饲料油水平对小龙虾的存活率、肥满度和肝体指数没有显著影响（P>0.05）。随着饲料脂质水平的增加，血清中的总抗氧化能力和谷胱甘肽过氧化物酶活性呈先上升后下降的趋势，且在投喂L6饲料的小龙虾中酶活性最高。肠道脂肪酶和胃蛋白酶活性在投喂L6饲料的小龙虾中显示出最高值。所有组中小龙虾的乙酰辅酶A羧化酶和肉碱棕榈酰转移酶-1含量没有显著差异（P>0.05）。L10饲料组小龙虾门水平的拟杆菌属和属水平的嗜冷杆菌属相对丰度显著降低，而门水平的厚壁菌门相对丰度与其他组相比显著增加（P<0.05）。总之，结果表明10.39%（L6饲料）的饲料脂质水平可诱导更好的生长性能、抗氧化能力和消化酶活性。肌肉中的大多数脂肪酸组成与饲料中的脂肪酸组成没有密切关系。此外，高饲料脂质水平改变了红螯螯虾肠道微生物群的组成和多样性。
