摘要
Abstract
This experiment was conducted to study the effect of Bacillus subtilis on growth performance and immunity in broilers. 200 one-day AA bilers with similar body weight were randomly divided into 5 groups with 4 replicates in each group, and with 10 broilers in each replicate. The groups received the same basal diet supplemented with 0, 2×105,5×105,8×105 and 1 × 106 CFU/g of Bacillus subtilis , respectively. The feeding trial lasted 42 days. The results showed as follows: in every test period, compared with the control group, the average daily gain in the group Ⅱ was higher, the F/G in group Ⅱ was lower, except at the age of 29 to 35 days. At the age of 36 to 42 days, the average daily gain in group Ⅱ increased significantly by 10. 25%(P<0. 05), the F/G in group Ⅱ decreased significantly by 14. 83% (P<0. 05) , at the age of 28 days, the spleen index was significant higher than those in the control group, higher above 31. 96% (P<0. 05) ,the bursa of fabricius index in group Ⅱ was significant higher than those in the control group, except at the age of 14 and 28 days, the antibody titer in group Ⅱ was higher than those in the control group, at the age of 28 and 35 days, higher above 16. 04% and 18. 09%, respectively(P< 0. 05);at the age of 21,35 and 42 days, the serum immunoglobulin G concentrations in group Ⅱ was higher those in control group, higher above 81. 94%, 46. 67% and 15. 63%, respectively(P<0. 05). In conclusion, adding 5 × 105 CFU/g Bacillus subtilis B7 in diet could improve the growth performance and enhance the immune function of broilers. These results indicated that the 5×105 CFU/g was the best supplementation.关键词
枯草芽孢杆菌/肉鸡/生长性能/免疫性能Key words
Bacillus subtilis /broilers/growth performance/immune function分类
农业科技
