Application of mix LPS-ELISA for monitoring of antibodies to major serogroups of Salmonella in animal

Mix LPS-ELISA법을 이용한 살모넬라균 복합감염항체 동시 모니터링

Salmonellosis caused by a number of serotypes of Salmonella is an infectious, acute or chronic, zoonotic disease and characterized by enteritis and diarrhea, septicemia in animal. In these studies we investigated the prevalent serotypes of Salmonella causing animal salmonellosis in Korea and the 71 strains of Salmonella spp. were isolated from materials such as mesenteric lymph nodes, fecal samples from slaughtered animal. With the identification test results, the most prevalent serotypes were, in order, S stanley 31 strains (43.7%), S typhimurium 19 strains (26.8%) and S montevideo 11 strains (15.5%), respectively. And we could establish the method for detection of antibodies to broad variety of Salmonella serotypes. Lipopolysaccharide(LPS) antigen extracted from Salmonella was more sensitive and specific than outer membrane protein antigen from that for detection of Salmonella antibody by using an indirect ELISA. The optimal concentration of antigen was 100ng/ml of LPS, the dilutions of conjugate and serum were 1 : 1,000~2,000 and 1 : 200~400, respectively. The mix LPS-ELISA which was used by mixing LPS from S typhimurium (group B), S choleraesuis (group C) and S enteritidis (group D) were more rapid and effective than that used LPS from individual strain for detection of Salmonella serogroup O4, O7 and O9 antibody at the same time. We could obtain the high values of optical density ($0.73{\pm}0.32$) by mix LPS-ELISA on the farm which had occurred salmonellosis, but very low values of $0.17{\pm}0.06$ on the negative farm of salmonellosis. So, the mix LPS-ELISA may be used to monitor the serological surveillance for the presence of infection with a number of serotypes of Salmonella and would be useful for prevention and control of salmonellosis in animal.