本研究旨在探讨丙氨酰-谷氨酰胺（Ala-Gln）缓解Diquat诱导的断奶仔猪氧化损伤的影响。试验采用双因子设计，选取24头健康状况良好、胎次相近的21日龄断奶仔猪，首先随机分成2个组，每组12个重复，每个重复1头猪，2个组分别饲喂基础饲粮和基础饲粮+0.3% Ala-Gln的试验饲粮。预饲喂7 d后，在前期饲喂基础上，将仔猪分成4个组，每组6个重复，每个重复1头猪，分别为基础饲粮组、基础饲粮+0.3% Ala-Gln组、基础饲粮应激组、基础饲粮+0.3% Ala-Gln应激组。应激组通过腹腔注射8 mg/kg BW Diquat模拟仔猪氧化应激，而未应激组则注射等量的灭菌生理盐水。试验期7 d。结果表明：1）仔猪氧化应激状态下，与基础饲粮应激组相比，饲粮中添加Ala-Gln显著提高了血清谷氨酰胺（Gln）、谷胱甘肽（GSH）含量和谷胱甘肽过氧化物酶（GSH-Px）、总超氧化物歧化酶（T-SOD）活性以及总抗氧化能力（T-AOC）（P<0.05）。2）仔猪正常生理状态和氧化应激状态下，与相应基础饲粮组和基础饲粮应激组相比，饲粮中添加Ala-Gln显著提高了空肠GSH-Px活性和T-AOC（P<0.05），显著降低了丙二醛（MDA）含量（P<0.05）；饲粮中添加Ala-Gln显著提高了肝脏GSH-Px活性和T-AOC（P<0.05），显著降低了MDA含量（P<0.05）。3）仔猪氧化应激状态下，与基础饲粮应激组相比，饲粮中添加Ala-Gln显著提高了肝脏中谷胱甘肽过氧化物酶4（GPx4）mRNA表达量（P<0.05），显著降低了超氧化物歧化酶1（SOD1）mRNA表达量（P<0.05）。由此可知，仔猪正常生理状态和氧化应激状态下，饲粮中添加Ala-Gln可提高仔猪抗氧化能力，降低MDA含量，从而减缓氧化应激对断奶仔猪机体组织的损伤；且在氧化应激状态下效果更为显著。

This experiment was conducted to study the effects of alanyl-glutamine (Ala-Gln) alleviate oxidative damage induced by Diquat of weaned piglets. The method of double-factor design is adopted. Twenty four piglets with health condition and similar parity weaned at 21 days of age were randomly divided into 2 groups with 12 replicates in each group and 1 pig in each replicate. Pigs in two groups were fed control diet and control diet+0.30% Ala-Gln, respectively. After 7 days pre feeding, based on the prophase feeding, the 24 piglets were randomly divided into 4 groups with 6 replicates in each group and 1 pig in each replicate. The four groups were basal diet group, basal diet+0.3% Ala-Gln group, basal diet stress group and basal diet+0.3% Ala-Gln stress group, respectively. Piglet oxidative stress was simulated by intraperitoneal injection of 8 mg/kg BW Diquat, and the unstressed groups were injected with the same volume of sterilized saline. The experiment lasted for 7 days. The results showed as follows:1) piglets under oxidative stress state, compare with the basal diet stress group, dietary supplemented with Ala-Gln significantly increased the contents of glutamine (Gln), glutathione (GSH) and activities of glutathione peroxidase (GSH-Px), total superoxide dismutase (T-SOD) and total antioxidant capacity (T-AOC) in serum (P<0.05). 2) Piglets under normal physiological state and oxidative stress state, compared with corresponding basal diet group and basal diet stress group, dietary supplemented with Ala-Gln significantly increased the GSH-Px activity and T-AOC in jejunum (P<0.05), and significantly decreased the malondialdehyde (MDA) content (P<0.05); dietary supplemented with Ala-Gln significantly increased the GSH-Px activity and T-AOC in liver (P<0.05), and significantly decreased the malondialdehyde (MDA) content (P<0.05). 3) Piglets under oxidative stress state, compare with the basal diet stress group, dietary supplemented with Ala-Gln significantly increased the liver glutathione peroxidase 4 (GPx4) mRNA expression (P<0.05), and significantly decreased the superoxide dismutase 1 (SOD1) mRNA expression (P<0.05). These findings indicate that piglets under normal physiological state and oxidative stress state, diets supplemented with Ala-Gln can improve antioxidant capacity and decrease MDA content of piglets, and to alleviate the organism tissue damage of oxidative stress of weaned piglets, especially under oxidative stress state.