Aspecros biomorfológicos de Hammondia heydorni (Tadros & Laarman, 1976) Dubey, 1977 (Apicomplexa: Sarcocystidae)

Abstract

Biomorphological aspects of natural and experimental Hammondia heydorni infections were studied in carnivores and ruminants. The prepatent and patent periods varied in different infections, but the sporulation time of the oocysts was 24 hours in enviromental temperature at 27-32°C, as those submited to controled temperature of 25 ± 1°C. The morphological index of the oocysts from differents hosts confirmed the spherical or subspherical form. In some cases differences of average size of the oocysts originated from samples of different hosts were significant ar level of 5%, however, these differences should be considered as intraspecific variations. N o clinical signs nor pathological findings were observed in infected animals. Histopathological examinations of muscle tissues from ruminants showed forms of the parasite similar to monozoic xvii. cysts, and in the immunofluorescence these parasites had a banana-shaped form. Smears of the small intestine, stained with Giemsa, demonstrated forms of the parasite characterized as meronts, merozoites, macro and microgametocytes.