Isolation and transmission of Cowdria ruminantium (causal agent of heartwater disease) in Blue Nile Province, Sudan.

Heartwater was diagnosed in sheep at the Umm Banein Livestock Research Station, Blue Nile Province, Sudan. Cowdria ruminantium was isolated from sheep by subinoculation of blood into a goat. Adult Amblyomma lepidum ticks fed as nymphs on this goat transmitted heartwater to a Friesian (Bos taurus) calf. Brain stabilates from this calf, either snap-frozen into liquid nitrogen or frozen slowly in a deepfreezer at -70 degrees C, with DMSO as cryoprotectant, were infective to cattle when inoculated subcutaneously.