Sarcocystis in feces of coyotes from Montana: prevalence and experimental transmission to sheep and cattle
Dubey, J.P.; Fayer, R.; Seesee, F.M.
Journal of the American Veterinary Medical Association 173(9): 1167-1170
1978
ISSN/ISBN: 0003-1488 PMID: 104939 Document Number: 129654
Of 169 faecal samples from coyotes from Montana, USA, 52.7% had Sarcocystis sporocysts, 3% had Isospora ohioensis-like oocysts, 1.8% had Isospora canis-like oocysts, 3% had Hammondia heydorni-like oocysts, and 8.8% had Eimeria sp. oocysts. Sarcocystis sporocysts measured 12 to 16 X 7.5 to 10 mu m. 106 sporocysts from coyotes were orally inoculated into each of 2 sheep and 2 cattle; one sheep and 2 cattle were kept as uninoculated controls. Both inoculated sheep became pyretic, anorectic, and anaemic. Histological specimens revealed myositis in both sheep and a high number of Sarcocystis cysts in one sheep. The control sheep remained healthy; histological specimens contained cysts without myositis, and fewer bradyzoites were recovered from pooled organs of the control sheep than from those of the inoculated sheep. All 4 cattle appeared normal until autopsy, 168 days after inoculation. More Sarcocystis cysts were found in histological sections of heart, skeletal muscle, and tongue of inoculated cattle than in histological specimens from uninoculated cattle, but the numbers of bradyzoites recovered from digested organs of inoculated and control cattle were not markedly different. Because coyotes may eat a great variety of intermediate hosts of Sarcocystis species, it could not be determined how many species of Sarcocystis were in the observed samples. The results indicated that coyotes are a source of ovine Sarcocystis and possibly bovine Sarcocystis in Montana. [AS].