The disruption of the dipping of cattle in Zimbabwe for the control of tick vectors demonstrated the dangers of creating herds with little or no natural immunity to tick-borne diseases. It is known that immunity to the tick-borne diseases heartwater (caused by Cowdria ruminantium), African redwater ...

The transfer of larvae and adult males of Boophilus microplus (Can.) from 2 infested to 2 uninfested cattle was demonstrated under field conditions in a 0.7-ha paddock in Zimbabwe. The role of host-to-host transfers in the transmission and epidemiology of anaplasmosis and babesiosis is discussed.

Adults of Amblyomma hebraeum Koch collected from cattle as engorged nymphs in 7 Tribal Trust Lands (TTLs) in southern Zimbabwe were fed on heartwater-susceptible sheep. Ticks from 2 of the TTLs transmitted Cowdria ruminantium, the causative agent of the disease. These findings provide indirect...

Between April 1980 and July 1981 serum samples were collected from 30 cattle aged 1-3 years at each of 118 localities throughout Zimbabwe (63 communal farming areas and 55 commercial farms) and screened for antibodies to A. marginale by the capillary tube agglutination test. Tick samples were also...