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Studies on the pathophysiology of chronic ovine haemonchosis in Merino and Scottish Blackface lambs

Published online by Cambridge University Press:  06 April 2009

E. M. Abbott
Affiliation:
University of Glasgow Veterinary School, Bearsden Road, Glasgow G61 12H
J. J. Parkins
Affiliation:
University of Glasgow Veterinary School, Bearsden Road, Glasgow G61 12H
P. H. Holmes
Affiliation:
University of Glasgow Veterinary School, Bearsden Road, Glasgow G61 12H

Summary

An experiment was conducted to examine, under laboratory conditions, the pathophysiology of chronic ovine haemonchosis. In the present study, groups of Merino and Scottish Blackface lambs were maintained on a low plane of nutrition and infected with 50 Haemonchus contortus larvae/kg live weight. The parasitized lambs along with respective breed controls were examined over a 27-week period. In addition to the body weight, haematological and parasitological parameters, erythrokinetic, metabolic, digestibility and nitrogen balance studies were conducted in the early stages of the infection. The results demonstrated that a low level of infection with H. contortus in lambs on a poor plane of nutrition caused the development of a normochromic normocytic anaemia which was associated with a modest but significant increase in abomasal blood loss and slightly elevated erythropoiesis in both breeds relative to the controls. The level of anaemia, hypoproteinaemia and pathophysiological changes were more marked in the Merino lambs and they also had higher faecal egg counts than the Blackface lambs.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1984

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