evaluation of serological cross reactivity among three strains of vibriosis

Serological cross reaction is a phenomenon that has been observed among related and unrelated organisms that may have related antigenic determinants. serological cross reaction may help protection of animal toward cross reacting organisms. that means when vaccination is performed to protect an animal against a known pathogen may also get protected against pathogens that share cross reacting antigenic determinants with vaccine organisms. the aim of this study was to determine serological cross reaction if any among three different strains of vibrios those are vibrio harveyi, vibrio parahaemolyticus and vibrio alginolyticus. immune sera were produced against v.harveyi through immunization of balb/c mice, using formalinized v.harveyi bacteria along with complete and incomplete freund’s adjuvants through specific program. the obtained immune sera were pooled and used in plate micro agglutination test while using various doubling diluted pooled immune sera and formalinized bacteria of v.harveyi, v.parahaemolyticus and v.alginolyticus as antigens. charged micro agglutination plate was incubated at room temperature overnight and the next day agglutination if any was observed and recorded. results obtained indicate that there is serological cross reaction among these three strains of vibrios. the pooled immune sera dilution up to 1/64 cross reacted with v.parahaemolyticus and v.alginolyticus antigens while when v.harveyi antigen is used the reaction goes up to 1/1024 pooled immune sera dilution. presence of serological cross reaction observed among these three strains of vibrio may help production of multivalent vaccine against vibriosis for use in aquaculture.