College of Animal Science, South China Agricultural University/Guangdong Provincial Key Laboratory of Animal Nutrition Control/Guangdong Laboratory for Lingnan Modern Agriculture/State Key Laboratory of Livestock and Poultry Breeding, Guangzhou, China.
J Sci Food Agric. 2023 Jul;103(9):4649-4659. doi: 10.1002/jsfa.12562. Epub 2023 Apr 6.
Probiotics comprise effective feed additives that can replace antibiotics in animal livestock production. However, mono-strain probiotics appear less effective because of their instability. Therefore, the present study aimed to investigate dietary supplementation with compound probiotics (CPP) on growth performance, diarrhea rate and intestinal mucosal barrier, as well as the possible molecular mechanism, in chicks. In total, 360 1-day-old chicks of the Hy-Line Brown Chicks were randomly divided into the control group (CON, basal diet), chlortetracycline group (500 mg kg CTC) and compound probiotics group (1000 mg kg CPP, consisting of Bacillus subtilis, Bacillus licheniformis, Enterococcus faecium and yeast). The experiment period was 56 days.
The results showed that, in comparison with the CON group, CPP significantly increased the average daily feed intake and average daily gain of chicks and reduced diarrhea (P < 0.05). The probiotic group exhibited increased immune organ (i.e. spleen and thymus) mass and increased levels of serum immunoglobulin (Ig)A, IgM and IgG (P < 0.05) compared to the CTC group. In addition, the jejunal mass and morphology were improved in the probiotic group (P < 0.05). Moreover, CPP reinforced jejunal barrier function, as indicated by increased transepithelial electrical resistance, protein expression of occludin and claudin-1, and diamine oxidase levels in the jejunum (P < 0.05). Likewise, enhanced fluorescence signals of proliferating cell nuclear antigen-labeled mitotic cells and villin-labeled absorptive cells in the jejunum (P < 0.05) suggested that CPP promoted intestinal stem cells activity. Mechanistically, the Wnt/β-catenin signaling pathway, including β-catenin, TCF4, c-Myc, cyclin D1 and Lgr5, was amplified in the jejunum by CPP addition (P < 0.05).
The present study demonstrated that dietary supplementation with CPP reinforced the jejunal epithelial integrity by activating Wnt/β-catenin signaling and enhanced immune function in chicks. © 2023 Society of Chemical Industry.
益生菌是一种有效的饲料添加剂，可以替代动物养殖中的抗生素。然而，由于其不稳定性，单菌株益生菌的效果似乎较差。因此，本研究旨在探讨复合益生菌（CPP）对小鸡生长性能、腹泻率和肠道黏膜屏障的影响，以及可能的分子机制。共选用 360 只 1 日龄海兰褐小鸡，随机分为对照组（CON，基础日粮）、金霉素组（CTC500mg/kg）和复合益生菌组（CPP1000mg/kg，由枯草芽孢杆菌、地衣芽孢杆菌、粪肠球菌和酵母组成）。试验期为 56 天。
与 CON 组相比，CPP 显著提高了小鸡的平均日采食量和平均日增重，降低了腹泻率（P<0.05）。与 CTC 组相比，益生菌组小鸡的免疫器官（脾和胸腺）质量增加，血清免疫球蛋白（Ig）A、IgM 和 IgG 水平升高（P<0.05）。此外，益生菌组的空肠质量和形态得到改善（P<0.05）。此外，CPP 增强了空肠屏障功能，表现为跨上皮电阻增加，occludin 和 claudin-1 蛋白表达增加，空肠中二胺氧化酶水平升高（P<0.05）。同样，空肠中增殖细胞核抗原标记有丝分裂细胞和微绒毛蛋白标记吸收细胞的荧光信号增强（P<0.05）表明 CPP 促进了肠道干细胞的活性。在机制上，CPP 增加了空肠中 Wnt/β-catenin 信号通路，包括β-catenin、TCF4、c-Myc、cyclin D1 和 Lgr5 的表达（P<0.05）。
本研究表明，CPP 通过激活 Wnt/β-catenin 信号通路增强了小鸡空肠上皮的完整性，并增强了小鸡的免疫功能。© 2023 化学工业协会。
