The development of Plasmodium gallinaceum infections in chickens following single infections with three different dose levels.

In the present study, groups of 5-day-old chickens were inoculated intravenously with approximately 10(6), 10(4) or 10(2) P. gallinaceum-infected erythrocytes. The outcome of disease in relation to dose level was evaluated in terms of number of parasitized erythrocytes, change in number of erythrocytes, pathological changes of organs and the course of exo-erythrocytic stages of the parasite in various organs over a period of 8 weeks. Mean weight gain and mortality were also recorded. With regard to differences between the size of the inoculation dose and the severity of disease, relationships could be observed in relation to clinical signs, mortality, prepatent period, exo-erythrocytic parasites and severity of pathological changes in organs, but in relation to weight gain, erythrocyte loss and number of parasitized erythrocytes no relationships were observed.