Comparison of Mycoplasma synoviae hemagglutinating antigens by the hemagglutination-inhibition test.

Mycoplasma synoviae (MS) strains were isolated from the trachea of hens from MS-positive broiler breeder flocks having progeny condemnations due to airsacculitis. Hemagglutinating (HA) antigens were made from several strains. The HA antigen made from the 95th medium passage of MS FMT strain was compared with that of the standard MS WVU 1853 strain by the hemagglutination-inhibition (HI) test. Sixty-six sera from 10 MS-positive flocks, 4 Mycoplasma gallisepticum (MG)-positive sera, and 7 normal sera were used in the HI test. The geometric mean (GM) HI titer with MS WVU 1853 antigen was 98.69 on 66 sera from 10 MS-positive flocks, whereas the GM HI titer with MS FMT antigen was 226.21.