Pang Xiyuan, Miao Zhiqiang, Dong Yuanyang, Cheng Huiyu, Xin Xiangqi, Wu Yuan, Han Miaomiao, Su Yuan, Yuan Jianmin, Shao Yuxin, Yan Lei, Li Jianhui
College of Animal Sciences, Shanxi Agricultural University, Taigu, China.
College of Animal Sciences and Technology, China Agricultural University, Beijing, China.
Front Pharmacol. 2023 Feb 15;14:1120718. doi: 10.3389/fphar.2023.1120718. eCollection 2023.
In this study, we investigated the effect of dietary methionine restriction (MR) on the antioxidant function and inflammatory responses in lipopolysaccharide (LPS)-challenged broilers reared at high stocking density. A total of 504 one-day-old male Arbor Acre broiler chickens were randomly divided into four treatments: 1) CON group, broilers fed a basal diet; 2) LPS group, LPS-challenged broilers fed a basal diet; 3) MR1 group, LPS-challenged broilers fed a methionine-restricted diet (0.3% methionine); and 4) MR2 group, LPS-challenged broilers fed a methionine-restricted diet (0.4% methionine). LPS-challenged broilers were intraperitoneally injected with 1 mg/kg body weight (BW) of LPS at 17, 19, and 21 days of age, whereas the CON group was injected with sterile saline. The results showed that: LPS significantly increased the liver histopathological score ( < 0.05); LPS significantly decreased the serum total antioxidant capacity (T-AOC), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activity at 3 h after injection ( < 0.05); the LPS group had a higher content of Interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF)-α, but a lower content of IL-10 than the CON group in serum ( < 0.05). Compared with the LPS group, the MR1 diet increased catalase (CAT), SOD, and T-AOC, and the MR2 diet increased SOD and T-AOC at 3 h after injection in serum ( < 0.05). Only MR2 group displayed a significantly decreased liver histopathological score ( < 0.05) at 3 h, while MR1 and MR2 groups did so at 8 h. Both MR diets significantly decreased serum LPS, CORT, IL-1β, IL-6, and TNF-α contents, but increased IL-10 content ( < 0.05). Moreover, the MR1 group displayed significantly increased expression of nuclear factor erythroid 2-related factor 2 (), , and at 3 h; the MR2 group had a higher expression of Kelch-like ECH-associated protein 1 (), , and at 8 h ( < 0.05). In summary, MR can improve antioxidant capacity, immunological stress, and liver health in LPS-challenged broilers. The MR1 and MR2 groups experienced similar effects on relieving stress; however, MR1 alleviated oxidative stress more rapidly. It is suggested that precise regulation of methionine levels in poultry with stress may improve the immunity of broilers, reduce feed production costs, and increase production efficiency in the poultry industry.
在本研究中，我们调查了日粮蛋氨酸限制（MR）对高饲养密度饲养的脂多糖（LPS）攻击的肉鸡抗氧化功能和炎症反应的影响。总共504只1日龄雄性艾维茵肉鸡被随机分为4组处理：1）对照组，肉鸡饲喂基础日粮；2）LPS组，LPS攻击的肉鸡饲喂基础日粮；3）MR1组，LPS攻击的肉鸡饲喂蛋氨酸限制日粮（0.3%蛋氨酸）；4）MR2组，LPS攻击的肉鸡饲喂蛋氨酸限制日粮（0.4%蛋氨酸）。LPS攻击的肉鸡在17、19和21日龄时腹腔注射1mg/kg体重（BW）的LPS，而对照组注射无菌生理盐水。结果表明：LPS显著增加肝脏组织病理学评分（P<0.05）；LPS显著降低注射后3h血清总抗氧化能力（T-AOC）、超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GSH-Px）活性（P<0.05）；LPS组血清中白细胞介素（IL）-1β、IL-6和肿瘤坏死因子-α（TNF）-α含量高于对照组，但IL-10含量低于对照组（P<0.05）。与LPS组相比，MR1日粮在注射后3h增加了过氧化氢酶（CAT）、SOD和T-AOC，MR2日粮增加了SOD和T-AOC（P<0.05）。仅MR2组在3h时肝脏组织病理学评分显著降低（P<0.05），而MR1和MR2组在8h时降低。两种MR日粮均显著降低血清LPS、CORT、IL-1β、IL-6和TNF-α含量，但增加IL-10含量（P<0.05）。此外，MR1组在3h时核因子E2相关因子2（Nrf2）、HO-1和NQO1的表达显著增加；MR2组在8h时kelch样ECH相关蛋白1（Keap1）、HO-1和NQO1的表达较高（P<0.05）。总之，MR可以提高LPS攻击的肉鸡的抗氧化能力、免疫应激和肝脏健康。MR1和MR2组在缓解应激方面效果相似；然而，MR1能更快地减轻氧化应激。建议精准调控应激家禽的蛋氨酸水平可提高肉鸡免疫力，降低饲料生产成本，提高家禽业生产效率。
