Badania nad toksoplazmozą drobiu. I. Przebieg doświadczalnej inwazjii u kur, ze szczególnym uwzględnieniem doustnej drogi zarażenia

The experiments were made on 180 hens aged from 1 day to 10 weeks. The animals were infected peroral, subcutaneously or intraperitoneally. The material for infection (RH strain) was used as exudate of mice (trophozoite) or as organs of rats or rabbits infected a year ago (cysts). Investigated was also the possibility of infection in healthy hens through direct contact with diseased ones. The items taken in consideration were as follows: (1) clinical picture, (2) hematologic examinations includimg number of erythrocytes, leukocytes, white cell count, (3) serologic studies using complement fixation and dye tests, (4) effect of food on the mechanism by which hens get infected per os (alkaline, neutral or acid reaction), (5) anatomo-pathologic, microscopic studies and isolation of strain. The results obtained prompt the following conclusions: (1) experimental toxoplasmosis of hens is difficult to induce and the moment of infection food seems to play a major role in the mechanism of infection. The mortality of hens is lower than in other animals infected in the same way and conditions, and even spontaneous cure may occasionally take place; (2) in peroral infection food seems to play a major role in the mechanism of infection. The administration of alkaline food increases the chance of infection; (3) in experimental conditions healthy hens may contract infection from diseased ones through direct contact; (4) hematologic studies do not seem to be of important diagnostic value, whereas the reduction in the number of erythrocytes may indieate an evolution of pathologic process; (5) Serologically (CFT and DT) the presence of antibodies is not an invariable finding, the positive reactions showing comparatively low titres.