Brown-headed cowbirds (Molothrus ater) harbor Sarcocystis neurona and act as intermediate hosts.

We tested the hypothesis that brown-headed cowbirds (Molothrus ater) harbor Sarcocystis neurona, the agent of equine protozoal myeloencephalitis (EPM), and act as intermediate hosts for this parasite. In summer 1999, wild caught brown-headed cowbirds were collected and necropsied to determine infection rate with Sarcocystis spp. by macroscopic inspection.

Effect of intermittent oral administration of ponazuril on experimental Sarcocystis neurona infection of horses.

Objective: To evaluate the effect of intermittent oral administration of ponazuril on immunoconversion against Sarcocystis neurona in horses inoculated intragastrically with S neurona sporocysts.

Animals: 20 healthy horses that were seronegative for S neurona-specific IgG.

Procedures: 5 control horses were neither inoculated with sporocysts nor treated.

Effect of a single dose of ponazuril on neural infection and clinical disease in Sarcocystis neurona-challenged interferon-gamma knockout mice.

Interferon gamma-knockout mice were challenged with 5000 Sarcocystis neurona sporocysts acquired from a naturally infected opossum. Ponazuril was administered once, by gavage, at day 1, 3, 7, 10, or 14 post-infection (pi). Ponazuril was given at either 20 or 200mg/kg.

Sarcocystis neurona: parasitemia in a severe combined immunodeficient (SCID) horse fed sporocysts.

Sarcocystis neurona was isolated from the blood of a 5-month-old Arabian foal with severe combined immunodeficiency. The foal had been inoculated approximately 3 weeks previously with 5 x 10(5) sporocysts that were isolated from the intestines of an opossum and identified by restriction enzyme analysis of PCR products as S. neurona.

The nine-banded armadillo (Dasypus novemcinctus) is an intermediate host for Sarcocystis neurona.

The nine-banded armadillo (Dasypus novemcinctus) is an intermediate host of at least three species of Sarcocystis, Sarcocystis dasypi, Sarcocystis diminuta, and an unidentified species; however, life cycles of these species have not been determined. Following feeding of armadillo muscles containing sarcocysts to the Virginia opossum (Didelphis virginiana), the opossums shed sporulated Sarcocystis sporocysts in their faeces. Mean dimensions for sporocysts were 11.