After weaning, piglets suffer from various stresses, and their immune function declines, causing diarrhoea and death. In recent years, the intestinal health of piglets has been a hot topic in the field of swine nutrition and feedstuff research. The present work aimed to investigate the effects of Clostridium butyricum (C. butyricum) on plasma immune function, antioxidant activity and plasma metabolomics of weaned piglets. A total of 90 weaning piglets of average weight (6.22 ± 0.24 kg BW) and 28±2 days old were randomly divided into three groups: control diet, control diet + 0.1 g/kg antibiotic (colistin sulphate), and control diet + 5 × 10⁸ CFU/kg C. butyricum. The pigs were divided into 6 pens per group with 5 piglets per pen for 21 days. Our results showed that the diet supplemented with 5 × 10⁸ CFU/kg C. butyricum significantly reduced the levels of plasma glucose, total protein, high-density lipoprotein, phosphorus, IL-6, TNF-α, MDA and increased the levels of albumin, triglyceride, low-density lipoprotein, IgG, C3, SOD activity, T-AOC in the plasma (P<0.05). There were seventeen kinds of differential metabolites were obtained by qualitative comparison of mass spectrometry (P<0.05). we conjectured that C. butyricum's role in immunity of weaned piglets may be mainly realized through the taurine and hypotaurine metabolism pathways (P=0.07). Based on the Spearman's rho correlation analysis, there were eleven differential metabolites (|ρ|≧0.60, P≦0.05) among significant plasma biochemical indexes, immune indexes, antioxidant enzyme activity and plasma metabolites. They were UMP, melanin, L-valine, thiamine(1+) diphosphate chloride, vanillylmandelic acid, L-methionine, bis(2-ethylhexyl) phthalate, Phosphatidylethanolamine lyso 18:0, (R)-octopamine, 3-amino-2-naphthoic acid and galactitol, respectively. To sum up, C. butyricum can improve the immune performance and antioxidant enzyme activity of weaned piglets and can be considered as a potential substitute for antibiotics.

断奶后，仔猪遭受各种压力，其免疫功能下降，导致腹泻和死亡。近年来，仔猪的肠道健康一直是猪营养和饲料研究领域的热门话题。本工作旨在调查酪酸梭状芽胞杆菌（C.butyricum）对断奶仔猪血浆免疫功能，抗氧化活性和血浆代谢组学的影响。将90头平均体重（6.22±0.24 kg BW）和28±2天大的断奶仔猪随机分为三组：对照日粮，对照日粮+ 0.1 g / kg抗生素（硫酸钴素）和对照日粮+ 5 ×10 ⁸ CFU / kg丁酸梭菌。将猪分为每组6只，每只猪5头，持续21天。我们的结果表明，日粮中添加5×10 ⁸ CFU / kg丁酸酪氨酸显着降低血浆葡萄糖，总蛋白，高密度脂蛋白，磷，IL-6，TNF-α，MDA的水平，并增加血浆中白蛋白，甘油三酸酯，低密度脂蛋白，IgG，C3，SOD活性，T-AOC（P <0.05）。质谱的定性比较获得了十七种差异代谢物（P <0.05）。我们推测丁酸梭菌在断奶仔猪免疫中的作用可能主要通过牛磺酸和牛磺酸的代谢途径来实现（P= 0.07）。基于所述斯皮尔曼的Rho相关分析，有11种差动代谢物（|ρ|≧0.60，P ≦0.05）显著等离子体生化指标，免疫指标，抗氧化酶活性和血浆代谢物中。它们是UMP，黑色素，L-缬氨酸，硫胺素（1+）二磷酸氯，香草锰酸，L-蛋氨酸，邻苯二甲酸双（2-乙基己基）酯，磷脂酰乙醇胺溶血素18：0，（R）-章鱼胺，3-氨基-2 -萘甲酸和半乳糖醇。综上所述，丁酸梭菌可以提高断奶仔猪的免疫性能和抗氧化酶活性，可以被认为是抗生素的潜在替代品。