State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Science, Beijing 100193, China.
Poult Sci. 2019 Mar 1;98(3):1403-1409. doi: 10.3382/ps/pey478.
Studies have shown that supplementing probiotics in a nasal spray can provide prophylaxis against upper respiratory tract infections. Previously, we found that spraying with Bacillus reduced the concentration of atmospheric ammonia and airborne microbiological aerosols in broiler houses. In the present study, we evaluated the effects of spraying with Bacillus amyloliquefaciens on the respiratory mucosal barrier in broilers. Two trails were conducted simultaneously in four environmentally controlled chambers. In each trail, 320 1-d-old male broilers were randomly assigned to control (CON) and B. amyloliquefaciens (BAQ) group. Eight cages containing 20 birds per cage were placed in two chambers. The BAQ group chambers were sprayed with B. amyloliquefaciens at 4 × 109 CFU/m2 each day for 42 d. Spraying with B. amyloliquefaciens increased average daily gain and average daily feed intake in broilers (P < 0.01), but had no effects on FCR (P > 0.05). The relative weights of the bursa (21 d) and spleen (42 d) were higher in the BAQ group (P < 0.05). The serum IgG, IgM (21 d), and IgA, Ig M (42 d) levels were improved in BAQ group (P < 0.05). The sIgA levels in tracheal lavage fluid were significantly higher in the BAQ group than the CON group (P < 0.05). Furthermore, treatment with BAQ downregulated IL-6 and IFN-γ (P < 0.05), but upregulated IL-2, occludin, and mucin-2 (P < 0.05). In addition, the number of acidic goblet cells was significantly higher in the tracheas of treated broilers than untreated broilers (P < 0.05). In conclusion, spraying with B. amyloliquefaciens may help to enhance the growth performance and improve the respiratory mucosal barrier in broiler chickens.
研究表明，在鼻腔喷雾中补充益生菌可以预防上呼吸道感染。此前，我们发现喷洒芽孢杆菌可以降低肉鸡舍内大气氨和空气微生物气溶胶的浓度。在本研究中，我们评估了喷洒解淀粉芽孢杆菌对肉鸡呼吸黏膜屏障的影响。同时在四个环境控制室进行了两项试验。在每项试验中，将 320 只 1 日龄雄性肉鸡随机分为对照组（CON）和解淀粉芽孢杆菌组（BAQ）。每组 8 个笼，每个笼装 20 只鸡。将 BAQ 组的笼舍每天用 4×109 CFU/m2 的解淀粉芽孢杆菌喷洒，共喷洒 42 天。喷洒解淀粉芽孢杆菌提高了肉鸡的平均日增重和平均日采食量（P＜0.01），但对饲料转化率（FCR）没有影响（P＞0.05）。BAQ 组的法氏囊（21 d）和脾脏（42 d）相对重量更高（P＜0.05）。BAQ 组的血清 IgG、IgM（21 d）和 IgA、IgM（42 d）水平提高（P＜0.05）。BAQ 组的气管冲洗液中分泌型 IgA（sIgA）水平显著高于 CON 组（P＜0.05）。此外，BAQ 处理下调了 IL-6 和 IFN-γ（P＜0.05），但上调了 IL-2、occludin 和 mucin-2（P＜0.05）。此外，处理组肉鸡气管中的酸性杯状细胞数量明显高于未处理组（P＜0.05）。综上所述，喷洒解淀粉芽孢杆菌可以帮助提高肉鸡的生长性能和改善呼吸黏膜屏障。
