College of Animal Science and Veterinary Medicine, Shandong Agricultural University, St, Taishan, Tai'an, Shandong, China.
Key Laboratory of Animal Bioengineering and Animal Disease of Shandong Province, Sino-German Cooperative Research Centre for Zoonosis of Animal Origin Shandong Province, 61 Daizong Road,, Tai'an, 271000, Shandong Province, China.
Probiotics Antimicrob Proteins. 2020 Dec;12(4):1385-1397. doi: 10.1007/s12602-020-09643-w.
A strain of Bacillus subtilis (B. subtilis) BYS2 was previously isolated from Mount Tai, which is located in Tai'an City in the Shandong Province of China. The strain was then stored in the Environmental Microbiology Laboratory at Shandong Agricultural University. To evaluate the effect of the bacterium preparation in broiler production, we fed the bacterium (10 CFU/g) to 1-day-old broilers and continued this feeding for 6 weeks to analyze its effect on growth and immune performance. We found that the average weight of the bacterium-fed group increased by 17.19% at weeks 5 compared to the control group (P < 0.05). The height of the villi in the duodenum and jejunum and the ratio of villi to crypt were significantly increased in the bacterium-fed group at weeks 5 (P < 0.05). Also, the IgG in the serum of broilers in the experimental group increased by 31.60% (P < 0.05) and IgM 30.52% (P < 0.05) compared with those in the control group. The expressions of the major pattern recognition receptors (PRRs), antiviral proteins, pro-inflammatory cytokines, and β-defensins were significantly higher than those in the control group (P < 0.05). Meanwhile, the bursa immune organ indices of broilers in the experimental group were significantly higher than those in the control group (P < 0.05). Also, after 5 weeks of continuous feeding, when infected with Escherichia coli (E. coli) O1K1 and Newcastle disease virus (NDV) F48E8, the content of bacteria and virus in tissues and organs of the experimental group decreased significantly, and the survival rate of infected chickens increased by 31.1% and 17.7%, respectively (P < 0.05). These results show that the anti-infective B. subtilis BYS2 could, to some extent, replace antibiotics to promote growth, improve innate immunity, and enhance disease resistance in broilers.
一株枯草芽孢杆菌（Bacillus subtilis）BYS2 此前从中国山东省泰安市的泰山分离得到，保藏于山东农业大学环境微生物实验室。为了评估该细菌制剂在肉鸡生产中的作用，我们将细菌（10 CFU/g）喂给 1 日龄肉鸡，并连续喂养 6 周，以分析其对生长和免疫性能的影响。结果发现，与对照组相比，第 5 周时细菌喂养组的平均体重增加了 17.19%（P<0.05）。第 5 周时，细菌喂养组的十二指肠和空肠绒毛高度以及绒毛与隐窝的比值均显著增加（P<0.05）。此外，实验组血清中 IgG 增加了 31.60%（P<0.05），IgM 增加了 30.52%（P<0.05），与对照组相比。主要模式识别受体（PRRs）、抗病毒蛋白、促炎细胞因子和β-防御素的表达显著高于对照组（P<0.05）。同时，实验组肉鸡的法氏囊免疫器官指数显著高于对照组（P<0.05）。此外，连续喂养 5 周后，当感染大肠杆菌（Escherichia coli）O1K1 和新城疫病毒（Newcastle disease virus）F48E8 时，实验组组织器官中的细菌和病毒含量显著降低，感染鸡的存活率分别提高了 31.1%和 17.7%（P<0.05）。这些结果表明，枯草芽孢杆菌 BYS2 具有一定的抗感染作用，可在一定程度上替代抗生素促进肉鸡生长，提高先天免疫，增强抗病力。
