Study On The Effects Of Dried Bacilluc On Performance And Structure Of The Bacterium Flora In Caecum Of Layers

Bacillus subtilis is one of the bacillus genus, The mycelius of bacteria in the growth process can produce hay rhzomorph, polymyxin, nystatin, gramicidin element et al active substances that can obviously inhibit pathogenic bacteria or endogenous infection of pathogenic bacteria. Its can quickly consume free oxygen in intestine and cause low-oxygen in intestine and promote the growth of beneficial anaerobic bacteria, and produce lactic acid et al organic acids that can reduce pH in intestine and indirectly inhibit the growth of pathogenic bacteria; It can stimulate the growth and development of immune organs and raise the level of immunoglobulin and antibodies, strengthen function of cellular immunity and humoral immune and reduce the occurrence of animal intestinal disease and obviously improve production performance and feed conversion rate of animal. Therefore, Bacillus subtilis is one of12microbial additives can be directly fed animal had published by thedepartment of agriculture. Selection Hay-Line Brown parents generation of layers were used as test objects, Different doses of bacillus subtilis was supplemented in ration of the layer to try to find out bacillus subtilis on effects of production performance and apparent digestibility of nutrition and the structure of the microorganism flora in caecum, Choossing the best adding dose of bacillus subtilis and providing a scientific basis for laying hens production. Experiment1:Studies of Dried Bacillus subtilis on effects of performance of layers.Fourth thousands Hay-Line layers at29-week-old were selected and divided randomly into4experiment groups, comparative studies of the adding different doses the Bacillus subtilis in ration on effects of performance of layers were conducted. The result of the study showed that could increase egg weight、laying rate when0.05%bacillus subtilis was added into the diets of layers and significantly raise the rate of fertilization、health young female chickens(p<0.05).Significantly reduce intake of the laying hens and feed-egg ratio and dead embryonic rate (p<0.05),but no significant effect on hatching rate. Experiment2:Studies of Bacillus subtilis on Effects of nutrition’s digestibility.of layers12healthy layers were randomly selected from each of the four treatments to carry out digestion and metabolic trials(all dung method),and measured apparent digestibility on feed energy,dry matter,calcium, utilization of phosphorus in every experimental group. The result hadve showed that:0.1%Bacillus subtilis group can significantly raise the apparent metabolizable energy, dry-matter digestibility(p<0.05),0.05%Bacillus subtilis group can significantly raise apparent digestibility of the protein,cacium, phosphorus(p<0.05). Experiment3:Studies of Bacillus subtilis on structure of the microorganism flora in caecumWhen38,48weeks,24healthy layers were randomly selected from the four treatments, Took out contents from the cecum and measured bacterium flora in the cecum. The result showed that:At38-week-old,0.1%bacillus subtilis in ration group could significantly reduce the population of Escherichia coli, Salmonella (p<0.05). At48-week-old,0.03%bacillus subtilis in ration group and0.05%bacillus subtilis in ration group could extremely significantly reduced the population of Escherichia coli, Salmonella (p<0.01), Significantly increased the population of lactobacilli (p<0.05).