Evaluation of genetically modified Lactobacillus reuteri Pg 4 containing xylanase gene as probiotic for poultry

• Main Authors: Shing-Fung Lai, 賴欣豐
• Other Authors: Bi, Yu
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/01855186234324280242

碩士 === 國立中興大學 === 畜產學系所 === 94 === The aim of this study was to evaluate the probiotic characterization of xylanase gene transferred Lactobacillus reuteri Pg 4 strain(TX-Pg 4), which isolated form GI tract of poultry. According to the in vitro assay, the Pg 4 and TX-Pg 4 strain showed the ability to survive after one and three hours under incubating in PBS (pH 2.0). In addition, Pg 4 and TX-Pg 4 strains could adhere to epithelium cell of crop of broiler in the adhesive ability assay. After incubated in MRS broth for 8 hours, the viable counts of TX-Pg 4 strain was up to 1010 CFU/mL. It showed that there was no different of probiotic characterics between Pg 4 and TX-Pg 4. By colorimeteric method and enzyme radial diffusion method, TX-Pg 4 showed the xylanase activity (Intracellulal and extracellual: 2.78 and 1.91 U/mL), but Pg 4 was undetable. In order to study the effect of the TX-Pg 4 strain supplement in the diet on the growth performance of broiler under normal environment. We process the TX-Pg 4 culture powder(1010 CFU/g)and supplemented in wheat-base diet. The results showed that Lactobacillus counts in the content of ileum and caecum of TX-Pg 4 group were higher than the control group on 21 and 42 day-old of broilers. And improved the body weight (P<0.05) on 21 day-old. By colony-PCR methods, we also confirmed the TX-Pg 4 exact in the content of GI of broiler.The concentration of total VFA and lactic acid of caecum content of treatment group had significantly higher than control group (P<0.05), the mucosa histology of the ileum of treatment group had the same result. The concentration of ammonia of digesta of caecum of treatment group also lower than control group(P<0.05). So as in the excreta. To summarize, after evaluated by in vitro and in vivo assay, the TX-Pg 4 strain could survive in the broiler GI tract with activity of xylanase. TX-Pg 4 strain powder supplement in barley diet could decrease digesta viscosity and significantly improved the body weight (P<0.05). According to the result of histology of the ileum, TX-Pg 4 had shown the benefit to GI of broiler. The TX-Pg 4 strain could be a multi-function candidate strain for probiotic use in broiler.