Eimeria leuckarti infection in foals.

The research article talks about the first reported incidence of Eimeria leuckarti infection in foals in Japan and its severe effects leading to the death of these foals linked with Strongylus vulgaris’s larval migration.

Study Background

• The study focuses on Eimeria leuckarti, a species of protozoan parasites that cause diseases in horses, and particularly foals. This is the first time such an infection is reported in Japan.
• Eimeria leuckarti infection was detected in seven foals aged 2 to 7 months. They were Thoroughbred or Angloarabian foals raised in the Hidaka district, Hokkaido. These foals were examined between 1970 and 1973.
• All these foals died due to severe alterations caused by the larval migration of Strongylus vulgaris, a common intestinal parasite in horses. It suggests a link between the Eimeria leuckarti infection and the severity of the larval migration.

Detailed Findings

• Protozoa of Eimeria leuckarti species were observed in the small intestine of all the foals. They were most commonly found in vacuoles (small cavities in the cell containing water, food, and waste matters) in the cytoplasm of monoclear cells in the lamina propria (a thin layer of connective tissue that forms part of the moist linings known as mucous membranes or mucosa).
• The monoclear cells containing the parasites were located at or near the tip of the villi, small finger-like projections in the intestines that increase the surface area for absorption of nutrients.
• The researchers noticed different stages of gametocytes (sex cells of the protozoa), oocysts (the tough-walled spores that produce these parasites), and microgametocytes (the male gametocytes).
• Upon infection, the nucleus of the cells was significantly enlarged, indicating the cellular response to the parasite was activated. However, the overall cellular response to the parasitic infection was minimal.

Implications

• The study identifies a new threat to horse rearing in Japan and highlights the need for further research to understand the relationships between Eimeria leuckarti and Strongylus vulgaris, and their combined impact on the health of foals.
• It also underscores the importance of adopting better diagnostic techniques and health management practices to detect and control such infections, thereby improving the survival and well-being of foals.