[Histomoniasis in pullet stock and its effect on later laying performance]

In a 17 1/2 weeks old pullet stock typhlohepatitis was diagnosed on the occasion of a stock examination by the poultry health service. Liver and gut of randomly selected pullets showed gross and histologic alterations as known in cases of typhlohepatitis in turkeys. Histomonads could be shown using both the PAS-reaction according to McManus and the silverstaining according to Grocott. In the following controls of the herd macroscopic visible alterations of the liver could not be seen, but some of the animals still exhibited gross lesions in the ceca. The course of the development of the herd from point-of-lay to the 9th month of laying period is described.