¹School of Medicine, Shihezi University, Shihezi, CHINA
²Research Institute of New Rural Development, Pingdingshan University, Pingdingshan, CHINA
³School of Animal Science and Technology, Shihezi University, Shihezi, CHINA
⁴First Affiliated Hospital of School of Medicine, Shihezi University, Shihezi, CHINA DOI : 10.9775/kvfd.2016.16803 There is a requirement to develop an novel vaccine to distinguish between vaccinated and infected animals after vaccination. Two mutants of Brucella melitensis M5-90Δbp261 and M5-90Δbp262, knockout of the fragments amino acids 55-152 and 22-185 respectively, were primarily generated. Then the two mutants were inoculated 7 weeks old BALB/c mice with 3.0 × 106 CFU/0.2 mL parent or mutant strains, Serum samples were evaluated by Rose Bengal plate tests, serum agglutination tests, colloidal gold immunochromatographic strips (ICS) coated with VirB5 or BP26 and indirect enzyme-linked immunosorbent assays. Spleen tissue samples were used to determine B. melitensis abundance at 10, 20, 30, and 40 days post-immunization (dpi). The serological results showed that the parent and mutant strains elicited a weak immunological reaction at 10–30 dpi. Fewer colony forming units (CFUs) were recovered from spleens in mutant strains group than the parent strain group during 20-40 post-immunization (dpi). The ICS were able to distinguish between the sera from mice immunized with either a parent or mutant strain of B. melitensis. These results indicate that the two mutants strain of B. melitensis have potentially perspectives in distinguishing infected animals from vaccination combined with ICS in this study. Keywords : Brucella melitensis, Distinguish, Vaccine, Colony forming units, ICS