How to treat horses suffering from piroplasmosis

Babesia equi in horses is a notifiable disease in parts of the US, but not in South Africa. It causes fatal anaemia, warns Dr Mac.

- Dr Mac.

Recently, I was notified about an outbreak of Babesia (Theileria) equi (piroplasmosis) in 163 horses in Texas. Babesia and Theileria are two scientific names for the same parasite. Certain US states legislate euthanasia rather than treatment.

The Internet debate was about how to treat horses successfully to prevent carriers. Generally, horses in the US are treated with tetracycline to remove the carrier state. This, in my opinion, is not sufficient. The parasite is carried by ticks, so tick control is essential.

As in South Africa, however, vector ticks also feed on cattle and wildlife.

Therefore, rather treat the horses and control vector ticks with ivermectin/ salt licks in the pasture. Also use cypermethrin spray-dip on livestock, horses and pet dogs to control vector ticks (Rhipicephalus and Hyalomma spp).

Equine piroplasmosis is not notifiable in South Africa and is a common cause of both acute and chronic disease. Signs of disease include a slightly elevated rectal temperature and pale or yellow gums. Urine is dark and the heart rate increases significantly. The haematocrit drops rapidly because