Dietary Threonine Promoted the Growth and Ovarian Development of the Red Swamp Crayfish ( Procambarus clarkii )

作者：Haihang Yao, Manxia Cao, Jianmin Zhang, Shouqi Xie, Kai Luo, Wenfu Xiao, Lixue Dong, Weihua Gao, Juan Tian · 发表于：Aquaculture Nutrition · 年份：2024 · DOI：10.1155/2024/5526963 · 被引用次数：11 · 研究领域：Aquaculture Nutrition and Growth、Neurobiology and Insect Physiology Research、Invertebrate Immune Response Mechanisms

To explore the effects of dietary threonine on growth and ovarian development of red swamp crayfish ( Procambarus clarkii ), crayfish (5.48 ± 0.19 g) were fed six isoproteic and isoenergetic diets with varying levels of threonine (7.16 g/kg (control), 9.19, 12.74, 16.44, 20.83, and 23.78 g/kg) for 8 weeks. The results showed that weight gain rate, feed conversion ratio, protein efficiency rate, protein deposition rate, and essential amino acid deposition rates obtained the optimal values when the dietary threonine level was 12.74 or 16.44 g/kg. Compared to the control group, the 12.74 g/kg group exhibited enhanced nonspecific immunity and antioxidant properties. The 16.44 g/kg group demonstrated a significant increase in the frequency of B cells and R cells in the hepatopancreas, the length and width of intestinal villi, and the activities of protease and lipase. It also showed elevated ecdysterone hormone, gonadal index (GI), cAMP content, and the relative abundance of beneficial intestinal microflora. Compared to the control group, the mRNA expression of mTOR , S6K1 , 4EBP1 , EcR , RXR , chitinase , PKA , Vg , cdc2 , and cyclin B was significantly upregulated, and the mRNA expression of MIH was significantly downregulated in the 16.44 g/kg group. Overall, optimal dietary threonine could improve intestinal health, regulate immune function, and enhance protein utilization, molting, and growth performance of red swamp crayfish. Additionally, it improved the synthesis of yolk s...