Serological diagnosis of pullorum disease with the microagglutination system

The application of a tetrazolium-stained Salmonella pullorum antigen in the microagglutination test is described and compared with the macroscopic tube agglutination test for detecting carriers of pullorum disease and fowl typhoid in chickens. Titers revealed by both testing procedures are similar; however, the microagglutination test is preferred because of the savings in time, space, and cost.