Effects And Mechanism Of Dietary B.licheniformis Supplementation On Performance Of Broilers And Weanling Pigs

Experiment 1: Efficacy of B.licheniformis as feed additive in broilers'feed and related mechanism540 1-day-old Avian male broilers were randomly allotted into 5 groups to evaluate the effects of a dried B.licheniformis on performance of broilers. Broilers in treatment 1 was fed a basal diet; the other treatments were basal diet +40mg/kg zinc bacitracin+10mg/kg colistinsulfate,or 1×10~9 CFU/kg dietary level B.licheniformis culture,or 2×10~9 CFU/kg,and 4×10~9 CFU/kg, respectively. The result of this study showed that there was an improvement in average daily gain , feed consumption and final weight of broilers during 0-21 days when 1×10~9 CFU/kg dietary level B.licheniformis culture was added (p<0.05) ,and there was also an increase in average daily gain, final weight during 43-51 days (p<0.1) . During 0-51 days, average daily gain was significantly improved (p<0.05) ; 2) Comparing low level of B.licheniformis group with antibiotics group, there was a trend to improve average daily gain and final weight (P>0.05).3) Excessive dose of B.licheniformis did not improve performance of broilers(P>0.05)supplemention with B.licheniformis significantly increase the activities of trypsin(P<0.05), improve the activities of a-amylase(P>0.05).Compared to control group,antibiotics group supplemented with B.licheniformis group significantly reduce the pH in jejunum(P<0.05).suitable dietary B.licheniformis level (1×10~9 CFU/kg) significantly decrease the pH in caecum (p<0.05). Supplemention with B.licheniformis did not significantly decrease Escherichia coli,and increase lactobacillus in cecum ,and feces.Experiment 2: Efficacy of B.licheniformis as feed additive in weanling pigs' diet120 35-day-old cross-bred(DoricxLandracexLarge white) weanling pigs were randomly allotted into 5 groups. The experiment was conducted to determine the influence of different dietary level B.licheniformis on performance,microorganisms in feces, serum total protein ,albumin,globulin. piglets in treatment 1 was fed a basal diet(Cu: 250mg/kg); the other treatments were fed a basal diet +50mg/kg zinc bacitracin+10mg/kg colistinsulfate,1×10~9 CFU/kg dietary level B.licheniformis culture,or 2x10 CFU/kg,and 4×10~9 CFU/kg, respectively. The result showed that suitable dietary B.licheniformis level significantly improve average daily gain of weanling pigs,increase the population of Escherichia coli,and reduce it of lactobacillus in feces, increase serum albumin also (P<0.05) ,reduce diarrhea incidences(P>0.05); Excessive dose of B.licheniformis culture did not improve performance of weanling pigs(P>0.05 ) except increase serum globulin (P<0.05)...