Yin Chao, Zhou Changming, Shi Yun, Ge Yangqin, Gao Xiaona, Wu Cong, Xu Zheng, Huang Cheng, Hu Guoliang, Liu Ping, Guo Xiaoquan
Jiangxi Provincial Key Laboratory for Animal Health, Institute of Animal Population Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, China.
Department of Mathematics and Statistics, Wright State University, Dayton, OH 45435, USA.
J Anim Sci. 2023 Jan 3;101. doi: 10.1093/jas/skad308.
The adverse effects of chronic heat stress (CHS)-induced fatty liver syndrome on laying hens during the egg-producing stages have been wildly documented. However, until nowadays, the CHS responses of growing laying hens as well as its alleviating effects of vitamin C are rarely reported. In this study, 12-wk-old laying hens were subjected to CHS at 36 °C for 10 h/d for 3 wk with or without dietary supplementation of 300 mg/kg vitamin C. Results showed that CHS significantly impaired the growth performances and the liver functions of birds, as characterized by reduced feed intake and body weight, increased hepatic lipid accumulation and serum concentrations of TG, ALT, and AST, as well as the abnormal expression patterns of the lipid metabolism-related genes. Vitamin C supplementation successfully mitigated the lipid accumulation, while showing no alleviating effect on the serum contents of ALT or AST, which are two key indicators of liver functions. Metabolomic analysis based on UPLC-Q-TOF/MS identified 173 differential metabolites from the HS and HSV group samples, and they are mainly enriched in the pathways related to the cellular components, vitamin and amino acid metabolism and energy substance metabolism. The results indicate that CHS-induced hepatic lipid deposition in growing laying hens is effectively alleviated by dietary supplementation of vitamin C, which is probably resulted from the alterations of hepatocellular metabolic patterns.
慢性热应激（CHS）诱导的脂肪肝综合征对产蛋期蛋鸡的不良影响已有大量文献记载。然而，迄今为止，关于育成蛋鸡的CHS反应及其维生素C的缓解作用鲜有报道。在本研究中，12周龄蛋鸡在36℃下接受10小时/天的CHS处理，持续3周，处理组蛋鸡的日粮中添加或不添加300mg/kg维生素C。结果表明，CHS显著损害了蛋鸡的生长性能和肝功能，表现为采食量和体重降低、肝脏脂质积累增加、血清甘油三酯（TG）、谷丙转氨酶（ALT）和谷草转氨酶（AST）浓度升高，以及脂质代谢相关基因的异常表达模式。补充维生素C成功减轻了脂质积累，但对肝功能的两个关键指标ALT或AST的血清含量没有缓解作用。基于超高效液相色谱-四极杆-飞行时间质谱（UPLC-Q-TOF/MS）的代谢组学分析从热应激（HS）组和热应激加维生素C（HSV）组样本中鉴定出173种差异代谢物，它们主要富集在与细胞成分、维生素和氨基酸代谢以及能量物质代谢相关的途径中。结果表明，日粮中补充维生素C可有效缓解CHS诱导的育成蛋鸡肝脏脂质沉积，这可能是肝细胞代谢模式改变的结果。
