The clinical pathology and pathophysiology of heartwater: a review.
This paper reviews the available literature on the clinical pathology and pathophysiology of heartwater and makes comparisons with unpublished results obtained from a recent study in experimentally-induced heartwater in calves. The pathophysiological changes seem to center on an increased capillary permeability the result of which is reflected most noticeably in cardiac and lung function. There is a marked drop in cardiac output in severe cases and some workers have recorded a severe drop in diastolic blood pressure in the advanced stage of the disease. Changes in lung function are variable, depending on the stage of the disease, and may change from a respiratory alkalosis in the early febrile stage to a respiratory acidosis in more advanced cases. The basic cause for the increased capillary permeability is not known. The main clinical pathological changes measured include a progressive anaemia, fluctuations in total and differential white cell count, of which an eosinopenia and a lymphocytosis are the most marked, increases in total bilirubin which coincide with darkening of plasma colour, and a drop in total serum proteins mostly shown in the albumin levels.
Van Amstel
S R
SR
Department of Medicine, Faculty of Veterinary Science, University of Pretoria, Onderstepoort.
Guthrie
A J
AJ
Reyers
F
F
Bertschinger
H
H
Oberem
P T
PT
Killeen
V M
VM
Matthee
O
O
D000818:Animals; D006357:Heartwater Disease / Q000097:blood* / Q000503:physiopathology