Black grain mycetoma (maduromycosis) in horses.

This research paper discusses the first ever recorded cases of black grain mycetoma, a fungal infection, found in horses, specifically a cross-bred pony and a Thoroughbred racehorse, in South Africa. The affected horses exhibited wart-like growths and deep-seated girth gall caused by the fungus similar to Curvularia geniculata observed in dogs.

Incidence of Black Grain Mycetoma in Horses

• The study was conducted in response to two cases of black grain mycetoma which manifested in horses. One of these was a cross-bred pony and the other a Thoroughbred racehorse.
• Black grain mycetoma is a type of fungal infection that, in these cases, led to physical deformities in the form of wart-like growths in one horse and a deep-seated girth gall in the other.
• This is significant as these are the first recorded instances of such an infection in horses in South Africa, marking a rare incidence of the disease in the region.

Examination of the Mycetoma Cases

• The study mainly focused on the examination of the granules in the infected tissue of the affected horses. These granules were found to have comparable pigmentation and structure to those engendered by Curvularia geniculata, a fungus usually seen in dogs.
• This observation leads to the assumption that the fungus may potentially affect multiple species, not restricting itself to a single species. It also brings forth the possibility of a new host animal for the said fungus.

Limitations of the Study

• However, the research also encountered a significant limitation. All the specimens used in the research were received preserved in formalin, which made it impossible to isolate the causative fungus for further study.
• This means that critical understanding about the species of the fungus that might have contributed to the black grain mycetoma in the horses, its characteristics or vulnerabilities could not be discerned through this study.