Antibody response of swine experimentally infected with Mycoplasma hyosynoviae

Antibody responses of swine inoculated intranasally with M. hyosynoviae were determined using complement-fixation, latex-agglutination, metabolic-inhibition, and mycoplasmacidal tests. The infected swine developed latex-agglutinating antibodies by 6 days postinoculation, complement-fixing and metabolic-inhibiting antibodies by 9-12 days, and mycoplasmacidal antibodies which were first detected from 12 days to 8 weeks postinoculation. Antibody titers persisted for as long as 6 months postinoculation. Complement-fixing and mycoplasmacidal antibodies were mainly IgG, and latex-agglutinating antibodies were IgM. Early metabolic-inhibiting antibodies were IgM while later antibodies were mainly IgG. None of the pigs had detectable complement-fixing antibodies to Mycoplasma hyorhinis.