Feed Research Institute of Chinese Academy of Agricultural Science, Key Laboratory of Feed Biotechnology of Agricultural Ministry and Rural Affairs, Beijing 100081, China.
Feed Research Institute of Chinese Academy of Agricultural Science, Key Laboratory of Feed Biotechnology of Agricultural Ministry and Rural Affairs, Beijing 100081, China; National Engineering Research Center of Biological Feed, Beijing 100081, China.
Poult Sci. 2021 Sep;100(9):101323. doi: 10.1016/j.psj.2021.101323. Epub 2021 Jun 10.
We studied the effects of Lactobacillus acidophilus (L. acidophilus) on the growth performance, intestinal morphology, barrier function, and immune response of broilers challenged with Escherichia coli O157 (E. Coli). A total of 360 1-day-old Cobb male broilers were tested in a 3 × 2 factorial arrangement with 3 dietary L. acidophilus levels (0, 5 × 10 CFU/kg, and 10 × 10 CFU/kg of diet) and 2 disease challenge treatments (control or E. coli challenged). Results showed that E. coli challenge decreased the ADG, ADFI, and BW of broilers from 15 to 21 d (P < 0.05), increased the jejunum intestinal wall thickness, and significantly increased the mortality rate. E. coli challenge significantly (P < 0.05) decreased the serum IgA and IgM contents and peripheral blood CD3+ T cell counts (P < 0.05), increased the serum CRP, DAO, and LPS levels at 21 d; upregulated the mRNA expression of iNOS, IL-8, IL-1β in the jejunum and iNOS in the spleen, and downregulated the occludin and ZO-1 mRNA expression in the ileum at 21 d compared with uninfected birds (P < 0.05). Dietary L. acidophilus supplementation consistently showed higher BW, ADG, ADFI, and jejunum and ileum V:C ratio at 14 d and 21 d in the presence and absence of E. coli challenge (P < 0.05). L. acidophilus supplementation reduced the mortality rate caused by E. coli challenge (P < 0.05), decreased the serum CRP, DAO, and LPS levels at 14 d and 21 d; upregulated the mRNA expression of occludin and ZO-1 in the jejunum and ileum, and downregulated the mRNA expression of iNOS, IL-8, and IL-1β in the jejunum in E. coli challenged birds at 21 d (P < 0.05). Dietary supplementation with L. acidophilus can improve the growth performance, intestinal health, and survival of broilers challenged with E. coli.
我们研究了嗜酸乳杆菌（Lactobacillus acidophilus）对大肠杆菌 O157（E. coli）感染肉鸡生长性能、肠道形态、屏障功能和免疫反应的影响。在一项 3×2 的析因试验中，共测试了 360 只 1 日龄科宝雄性肉鸡，其饲料中嗜酸乳杆菌水平（0、5×10 CFU/kg 和 10×10 CFU/kg 饲料）和 2 种疾病挑战处理（对照或大肠杆菌感染）存在 3 个因素。结果表明，大肠杆菌感染降低了 15 至 21 日龄肉鸡的平均日增重、平均日采食量和体重（P<0.05），增加了空肠肠壁厚度，显著提高了死亡率。大肠杆菌感染显著降低了血清 IgA 和 IgM 含量以及外周血 CD3+T 细胞计数（P<0.05），增加了 21 日龄时血清 CRP、DAO 和 LPS 水平；在感染的鸡中，上调了空肠组织中 iNOS、IL-8、IL-1β 和脾组织中 iNOS 的 mRNA 表达，下调了回肠组织中 occludin 和 ZO-1 的 mRNA 表达（P<0.05）。与未感染的鸡相比，在有无大肠杆菌感染的情况下，日粮中添加嗜酸乳杆菌在 14 日龄和 21 日龄时始终表现出更高的体重、平均日增重、平均日采食量和空肠及回肠的 V:C 比值（P<0.05）。嗜酸乳杆菌的添加降低了大肠杆菌感染引起的死亡率（P<0.05），降低了血清 CRP、DAO 和 LPS 水平在 14 日龄和 21 日龄时的水平；上调了感染鸡空肠和回肠中 occludin 和 ZO-1 的 mRNA 表达，下调了空肠中 iNOS、IL-8 和 IL-1β 的 mRNA 表达（P<0.05）。日粮中添加嗜酸乳杆菌可改善大肠杆菌感染肉鸡的生长性能、肠道健康和成活率。
