Immunization of pigs with an inactivated Mycoplasma hyopneumoniae vaccine (bacterin) generates hyperimmune serum that contains high concentrations of anti-M. hyopneumoniae IgG. Commercially available IgGELISA kits cannot distinguish between anti-M. hyopneumoniae IgG in inactivated bacterin-induced hyperimmune sera and convalescent sera resulting from natural M. hyopneumoniae infection. |