目的 研究抗菌肽PG-3对哺乳动物肠道屏障功能的影响，为畜牧业生产中抗生素的替代提供依据。 方法 选取36只6周龄雄性小鼠，随机分为3组（每组12只），即磷酸缓冲盐溶液组（对照CON组）、鼠伤寒沙门菌（ST）组、鼠伤寒沙门菌和抗菌肽复合组（ST+AMPS），连续饲喂14 d，测定MDA含量、SOD、GSH-Px、MPO活性。 结果 饲喂ST后，与CON组相比，MDA含量提高0.18 nmol/mg，SOD活性降低3.15 U/mg，MPO活性提高1.1 U/g，GSH-Px活性降低0.09 nmol/L。饲喂抗菌肽PG-3后，与CON组相比，MDA含量提高0.02 nmol/mg，SOD活性降低0.48 U/mg，MPO活性降低0.005 U/g，GSH-Px活性提高0.02 nmol/L。 结论 抗菌肽PG-3可以让感染鼠伤寒沙门菌的小鼠机体质量恢复到正常水平，有明显的抗菌抑菌作用，同时对动物机体抗氧化能力具有保护作用。

Objectives The effects of antimicrobial peptide PG-3 on the function of intestinal barrier in mammals were studied to provide a basis for the substitution of antibiotics in animal husbandry production and a feasible approach for improving the quality and efficiency of animal husbandry. Methods 36 male mice aged 6 weeks were randomly divided into three groups including the phosphate buffered saline solution group (control), the Salmonella typhimurium group (ST), and the Salmonella typhimurium combined with antimicrobial peptide PG-3 group (ST+AMPS), 12 mice in each group. The content of MDA and the activity of SOD, GSH-Px, MPO were measured after 14 days of continuous feeding. Results The content of MDA and the activity of MPO in ST increased by 0.18 nmol/mgprot and 1.1 U/g, the activity of SOD and GSH-Px in ST decreased by 3.15 U/mg and 0.09 nmol/L, compared with that in control. The content of MDA and the activity of GSH-Px in ST+AMPS increased by 0.02 nmol/mg and 0.02 nmol/L, the activity of SOD and MPO in ST+AMPS decreased by 0.48 U/mg and 0.005 U/g, compared with that in control. Conclusions Antimicrobial peptide PG-3 can restore the body weight of mice infected with Salmonella typhimurium to normal levels, with significant antibacterial and bacteriostatic effects, while protecting the antioxidant capacity of animals as well. It will provide a theoretical basis for the use of antimicrobial peptide PG-3 as a substitute for antibiotics in animal husbandry production.