| Abstract: | Sera from inbred SPF White Leghorn chickens at 6 weeks or 19-22 months of age did not have anti-OA agglutinins as determined by the passive HA reaction; 2-day-old chicks also lacked the anti-OA activity. Inbred chickens kept in SPF isolators for 6 weeks, then transferred to a conventional environment for 7 weeks, produced anti-OA agglutinins. Inbred White Leghorn adult chickens conventionally reared had a high anti-OA agglutinin titer. It appeared that natural anti-OA agglutinin s are elaborated in response to environmental pathogens in certain lines of chickens. The titer in the individual chicken appeared as early as 10 weeks and was maintained until old age. The presence of natural anti-OA agglutinins did not prevent egg-laying but appears to have delayed it. The HA reaction is specific and can be absorbed. |
