Detection of antibody to Mycoplasma synoviae by gel diffusion precipitation reaction using commercially available antigen for agglutination reaction

摘要

Serum samples from free-range pullets and hens 120-582 days of age on a farm were tested for antibodies to M. synoviae (MS) by gel diffusion precipitation (GDP) using commercially available antigen for rapid agglutination (RA). For each group, a sedimentation line fusing with that produced between the antigen and anti-MS immune chicken serum, appeared with some test sera of all age groups. Both RA and GDP positive reactions were observed in 1 of 16 and 15 of 20 cases of pullets aged 120 days and those aged 190 days respectively. Both-positive results were seen also in 14 of 20 and 13 of 20 sera from hens aged 405 days, and those aged 582 days respectively. No sera of 120-day-old pullets as well as 1 to 2 cases of other groups were negative in bothRA and GDP tests. 50% or 70% of sera showing false positive reactions in RA were positive in GDP except for those from the 120-day-old group. It is concluded that, while GDP is less sensitive for detection of antibodies at an early stage of MS infection, it might be sensitive enough at later stage of infection.