Animal experimental design to study the role of phage therapy in acute-non typhoidal Salmonellosis Co-investigator: Dr. Parameth Thiennimitr, M.D.,Ph.D. Address: Department of Microbiology, Faculty of Medicine, Chiang Mai University Species of animal: 6-8 weeks old female mouse (Mus musculus) C57BL6 strain Protocol (in brief): C57BL/6 mice will be purchased from Nomura Siam International. Mice will be acclimatized for at least 1 week before the experiment day. 24 hour before Salmonella enterica Typhimurium (strain IR715) infection, mouse will be orally gavaged with 20 mg streptomycin sulphate to allow subsequent STM IR715 to establish a colitis. Streptomycin-treated mice will be orally infected with 100 microlitr of 109 cfu/ml STM IR715 solution. Then, 100 microlitr of Salmonella phage solution will be orally gavaged to the infected mice for consecutively 3 days. On day 4 post infection, mice will be euthanized by CO2 and cervical dislocation. Mouse colon content, colon, spleen will be collected for further analysis. Control group (no treatment) of mice will be orally fed with normal saline solution as used as a vehicle for the experimental (phage therapy) groups. Animal protocol approval committee: All animal experiments conduct at Chiang Mai University will be approved by the Chiang Mai University Animal Care and Use Committee (CMU-ACUC). All animal experiments will be performed in the AAALAC-certified biosafety level (BSL) 2 facility located in Chiang Mai University. Numbers of animal in each group is 7. [Calculated followed Bernard, R. (2000). Fundamentals of biostatistics (5th ed). Duxbery: Thomson learning, 308, level of significance = 0.05)]