Effects Of Lactic Acid Bacteria And Bacillus Subtilis In Broiler Production

We aimed to evaluate the effect of Lactic acid bacteria(LAB) and Bacilllus subtilis(BS) on the broiler performance, the pH of different intestinal segments, the relative length of the intestine, the relative weight of the intestine and the slaughter performance. Verify the principle of LAB and BS improving the nutrient utilization and the growth on broiler chickens, and determine the specific values. Build the scientific basis theoretical for the economic benefit about adding different additives in broiler production.One thousand one hundred and fifty two 1- d- old mixed sex broilers were randomly allotted into 4 treatments for 6 weeks. The 4 dietary treatments: Control: Corn-soybean meal based die,feeding the based diet; Negative control: supplemented 40 mg/1000 kg bacitracin zinc(BZ) + 20 mg/1000 kg colistin sulfate(CS) to based diet; Test 1: supplemented 200 mg/1000 kg LAB to based diet; Test 2: supplemented 300 mg/1000 kg BS to based diet. The results: 1) The NC, LAB and BS had no statistically significant effect on performance of broilers(P > 0.05). 2) The NC could extremely significantly reduce the pH of gland stomach on 21 d(P < 0.01), and it could also significantly reduce the p H of ileum on 42 d( P < 0.05); The LAB could extremely significantly reduce the pH of gland stomach, duodenum and ileum on 21 d(P < 0.01), and it could also significantly reduce the pH of ileum on 42 d(P < 0.05); The BS could extremely significantly reduce the pH of muscular stomach, ileum on 21 d, and the pH of gland stomach on 42 d(P < 0.01). The BS could also significantly reduce the pH of ileum on 42 d(P < 0.05), and had the tendency to reduce the pH of jejunum on 21 d(P = 0.08); 3) The NC had no statistically significant effect on the relative length of the intestine( P > 0.05); The LAB and BS could both significantly increase the relative length of jejunum(P < 0.01), and had the tendency of the increase on the relative length of ileum( P = 0.09), and then had the significantly increase on the relative length of intestine(P < 0.01); The BS could also have the significantly increase on the relative length of du odenum(P < 0.01); 4) The NC, LAB and BS all had the tendency to increase the relative weight of the duodenum(P = 0.06); These three kinds of additives had no statistically significant effect on the relative weight of the Jejunum, the ileum and the intestine; 5) The NC, LAB and BS had no statistically significant effect on the slaughter performance of broilers(P > 0.05); Compared with NC, The BS had the tendency to increase the percentage of eviscerated yield(P = 0.06).Two hundred and seventy AA broilers which were 42 d from the earlier stage of experiment were randomly allotted into 3 treatments, and each of which had 90 broilers. The 3 dietary treatments: Test 1: Corn-soybean meal based diet; Test 2: Only for the corn; Test 3: Only for the wheat. The results: 1) The NC had no statistically significant effect on metabolic rate about the basal diet(P > 0.05); The LAB could significantly reduce the apparent metabolic rate and true metabolic rate about the basal diet on DM(P < 0.05), but had significantly increase the apparent metabolic rate and true metabolic rate about the basal diet on CP( P < 0.05); The BS could significantly increase the apparent metabolic rate and true metabolic rate about the basal diet on DM and CP(P < 0.05). It also could significantly increase the true metabolic rate about basal diet on GE(P < 0.05), and had tendency to increase the apparent metabolic rate about the basal diet on GE(P = 0.06). 2) The LAB had tendency to increase the apparent metabolic rate and true metabolic rate about the corn on DM(P = 0.08); The NC and BS had no statistically significant effect on the metabolic rate about the corn(P > 0.05). 3) The NC could extremely significantly reduce the apparent metabolic rate and true metabolic rate about the wheat on DM and GE(P < 0.01); The LAB had no statistically significant effect on the metabolic rate about the wheat(P > 0.05); The BS could extremely significantly reduce the apparent metabolic rate about the wheat on DM, and could extremely significantly reduce the true metabolic rate about the wheat on DM and GE(P < 0.01).