Improved culture conditions for Cowdria ruminantium (Rickettsiales), the agent of heartwater disease of domestic ruminants.

The causal agent of heartwater disease of domestic ruminants, Cowdria ruminantium, can, with difficulty, be isolated and passaged in lines of bovine endothelial cells grown in the presence of the Glasgow modification of Eagle's minimal essential medium. However, when Leibovitz's L-15 medium supplemented with 0.45% glucose at pH 6.0-6.5 is used as maintenance medium for these cells, isolation and serial passage may routinely be achieved.