Ultrastructural morphology of Cowdria ruminantium in midgut epithelial cells of adult Amblyomma hebraeum female ticks.
Amblyomma hebraeum male and female ticks, experimentally infected as larvae with the Ball 3 stock of Cowdria ruminantium, were fed on a heartwater susceptible sheep. The initial attachment of the males was required as a pre-requisite for female attachment. Reticulate bodies were the predominant morphologic form of Cowdria observed in gut epithelial cells after 1-3 days of feeding. Single intermediate bodies and no elementary bodies were observed. Organisms were found within a membrane-bound vacuole and each organism had a double-unit membrane. Infrequently colonies contained homogeneous electron-dense inclusions. Groups of Cowdria organisms within a haemocyte suggested a possible dissemination of organisms from the gut to various other tissues by haemocytes.
Veterinary Research Institute, Onderstepoort.
A
A
Hart
K M
KM
Kocan
J D
JD
Bezuidenhout
L
L
Prozesky
D000818:Animals; D016995:Ehrlichia ruminantium / Q000648:ultrastructure*; D004848:Epithelium / Q000382:microbiology; D005260:Female; D008297:Male; D013987:Ticks / Q000382:microbiology*