title: Reducing microbial ureolytic activity in the rumen by immunization against urease therein.
abstract: BACKGROUND
  Ureolytic activity of rumen bacteria leads to rapid urea conversion to ammonia in the rumen of dairy cows, resulting possible toxicity, excessive ammonia excretion to the environment, and poor nitrogen utilization. The present study investigated immunization of dairy cows against urease in the rumen as an approach to mitigate bacterial ureolytic activity therein.
  
  
  RESULTS
  Most alpha subunit of rumen urease (UreC) proteins shared very similar amino acid sequences, which were also highly similar to that of H. pylori. Anti-urease titers in the serum and the saliva of the immunized cows were evaluated following repeated immunization with the UreC of H. pylori as the vaccine. After the fourth booster, the vaccinated cows had a significantly reduced urease activity (by 17%) in the rumen than the control cows that were mock immunized cows. The anti-urease antibody significantly reduced ureolysis and corresponding ammonia formation in rumen fluid in vitro. Western blotting revealed that the H. pylori UreC had high immunological homology with the UreC from rumen bacteria.
  
  
  CONCLUSIONS
  Vaccine developed based on UreC of H. pylori can be a useful approach to decrease bacterial ureolysis in the rumen.
authors.affiliation: Ministry of Agriculture Laboratory of Quality & Safety Risk Assessment for Dairy Products (Beijing), Institute of Animal Science, Chinese Academy of Agricultural Sciences, No. 2 Yuanyingyuan West Road, Beijing, 100193, PR China. 13811307631@163.com.|State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, No. 2 Yuanyingyuan West Road, Beijing, 100193, PR China. 13811307631@163.com.
authors.forename: Shengguo
authors.initials: S
authors.lastname: Zhao
authors.affiliation: Ministry of Agriculture Laboratory of Quality & Safety Risk Assessment for Dairy Products (Beijing), Institute of Animal Science, Chinese Academy of Agricultural Sciences, No. 2 Yuanyingyuan West Road, Beijing, 100193, PR China. jiaqiwang@vip.163.com.|State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, No. 2 Yuanyingyuan West Road, Beijing, 100193, PR China. jiaqiwang@vip.163.com.
authors.forename: Jiaqi
authors.initials: J
authors.lastname: Wang
authors.affiliation: Ministry of Agriculture Laboratory of Quality & Safety Risk Assessment for Dairy Products (Beijing), Institute of Animal Science, Chinese Academy of Agricultural Sciences, No. 2 Yuanyingyuan West Road, Beijing, 100193, PR China. nanzheng.cn@gmail.com.|State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, No. 2 Yuanyingyuan West Road, Beijing, 100193, PR China. nanzheng.cn@gmail.com.
authors.forename: Nan
authors.initials: N
authors.lastname: Zheng
authors.affiliation: State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, No. 2 Yuanyingyuan West Road, Beijing, 100193, PR China. burdenpan@gmail.com.
authors.forename: Dengpan
authors.initials: D
authors.lastname: Bu
authors.affiliation: State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, No. 2 Yuanyingyuan West Road, Beijing, 100193, PR China. 13261990342@163.com.
authors.forename: Peng
authors.initials: P
authors.lastname: Sun
authors.affiliation: Department of Animal Sciences, The Ohio State University, Columbus, OH, 43210, USA. yu.226@osu.edu.
authors.forename: Zhongtang
authors.initials: Z
authors.lastname: Yu
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification / Q000201:enzymology*; D001428:Bacterial Vaccines / Q000276:immunology*; D002417:Cattle / Q000382:microbiology*; D015964:Gene Expression Regulation, Bacterial / Q000276:immunology; D015971:Gene Expression Regulation, Enzymologic / Q000276:immunology; D007114:Immunization; D012417:Rumen / Q000201:enzymology*; D014508:Urea / Q000378:metabolism*; D014510:Urease / Q000276:immunology* / Q000378:metabolism
chemical_list: D001428:Bacterial Vaccines; D014508:Urea; D014510:Urease