Preparation Of Probiotics And Its Effects On Performance、immunity And Intestinal Microecology Of Gushi Chickens

The purpose of this study was to screen out salivary Lactobacillus and Bacillus cereus which could live in simulated gastrointestinal tract of low p H and high concentration of bile salt environments from healthy poultry intestinal,and the salivary Lactobacillus with antibacterial activity 。 Mixed with Saccharomyces cerevisiae preserved in our laboratory in accordance with a ratio of 7:2:1(salivary Lactobacillus 9×108/g, Bacillus cereus 2.5×108/g, Saccharomyces cerevisiae 1.5×108/g)in the study,and then the compound probiotics were used to ferment soybean meal(soybean meal: bran =7:3) by 10% inoculation quantity under condition of 30 ℃for 72 hour。Dynamic changes of conventional nutrition indicators were monitored in the fermentation process。Subsequently,both probiotics fermented soybean meal and raw soybean meal made meal diet were reared in 1-day-old Gushi chickens for a period of 28 days,followed by the effects of probiotics fermented soybean meal on growth、immune functions、intestinal microflora and intestinal morphology of Gushi chickens were detected compared to the raw soybean meal。Experiment 1 : Isolation and Identification of Bile and Acid-resistant Lactobacillus and Bacillus and Lactobacillus with Antibacterial ActivityAcid-production Lactobacillus and high temperature-resistant Bacillus were isolated from healthy poultry intestines,strains were screened respectively by acid and bile tolerance and the antibacterial activity of Lactobacillus was determinated。At last,Lactobacillus and Bacillus which could live in simulated gastrointestinal tract were obtained and Lactobacillus with Antibacterial Activity。Furthermore, 16 S r RNA of isolated strains were amplified and aligned for identification and the phylogenetic trees of isolates were constructed by using MEGA5.0 for analysis。Salivary Lactobacillus and Bacillus cereus in accordance with test requirements were screened successfully。Experiment 2:Dynamic monitoring of conventional nutritional index in the process of probiotics fermented soybean mealThe concentration of salivary Lactobacillus culture suspension、Bacillus cereus suspension and Saccharomyces cerevisiae suspension were adjusted using Maxwell turbidity instrument 。In accordance with a ratio of 7:2:1(salivary Lactobacillus 9×108/g,Bacillus cereus 2.5×108/g,Saccharomyces cerevisiae 1.5×108/g)in the study,and then the compound probiotics were added to raw soybean meal(soybean meal: bran =7:3) by 10% inoculation quantity under the condition of moisture ranged 70%-90% at 30℃、 for 72 hour fermented。Ventilation and samples collection were operated in a sterile environments every 12 hours in order to detect the changes of conventional nutrition indicators in the process of fermentation。The results showed that:1)the moisture content maintained at about 37% throughout the fermentation process and no significant changes;2)changes of protein content during the whole fermentation process was firstly decreased and increased significantly(P < 0.05) subsequently, then maintained at a relatively high levels;3)p H values were significantly reduced in the 36 h fermentation later(P < 0.05), then was stable at low p H range; 4) viable content decreased significantly at first(P < 0.05), yet significantly increased(P < 0.05) at 36 h and the number of living bacteria maintained high;5) except threonine, the content of amino acid increased, and at the fermentation of 72 h, content of amino acids were significantly increased(P < 0.05)。Experiment 3:Effects of probiotics fermented soybean meal on growth、immune functions、intestinal microflora and intestinal morphology of Gushi chickensIn this study,96 1-day-old Gushi chickens were divided into two treatments randomly,four replications each treatment,which were fed with meal diets compared using fermented and raw soybean meal respectively。After the detection of growth performance at 1d、14d and 28 d,four chickens were taken randomly from each treatment and bled to death,measuring their immune organ index,separating various intestinal segments and collecting the contents in sterile environments。The results showed that:1)Probiotics fermented soybean meal(PFSM) significantly increased(P < 0.05)average daily gain of Gushi chickens in the whole trial period;2) PFSM significantly improved(P < 0.05)thymus index in the whole trial period and also significantly improved(P < 0.05) bursa index in the final period;3) PFSM sharply increased(P < 0.05) jejunum length of 28 d Gushi chickens and significantly improved(P < 0.05)duodenal weight of 14 d and ileum weight of 28d; 4)PFSM significantly increased(P < 0.05)the population of Lactobacillus of 14 d ileum and 28 d rectal in Gushi chickens, significantly reduced(P < 0.05) the population of Escherichia coli and salmonella of Gushi chickens, cecum;Along with the growth of age, the microflora of duodenum、jejunum and ileum tend to be balanced, and microbial species gradually increased latter。While the micro ecological diversity of cecum and rectum of late is superior to the early,the main microbial species of recycling bands were to Pseudomonas bacillus, bacillus and Lactobacillus; 5)PFSM significantly increased(P < 0.05)villus height of duodenal and rectal in Gushi chickens。The experimental results show that, the PFSM could promote the growth of Gushi chickens, improve the index of immune organs, promote the intestinal development in various degrees,facilitate the balance of intestinal microflora and microbial diversity of the large intestine,contribute to the development of intestinal villi in some extent。...