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Gastrointestinal nematode infection in sheep – a review of the alternatives to anthelmintics in parasite control

Published online by Cambridge University Press:  08 March 2007

G. Sayers  and
T. Sweeney
G. Sayers*
Affiliation:
School of Agriculture, Food Science and Veterinary Medicine & Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Ireland
T. Sweeney
Affiliation:
School of Agriculture, Food Science and Veterinary Medicine & Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Ireland
*
*Corresponding author: Email: [email protected]
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Abstract

Efforts to curb production losses caused by nematode parasitism in sheep have led to the development of a number of control methods to complement or replace anthelmintics. The need for alternative control measures stems from the emergence of anthelmintic-resistant parasitic nematodes with reports of multi-class resistance to these drugs now emerging. A number of these control methods such as predacious microfungi, protein supplementation, plant extracts in feed and vaccines have demonstrated potential to control infection but require development and examination under natural conditions. Breeding for natural resistance to nematode infection has already shown success in controlling the disease under natural conditions. Selection for resistance is currently based on fecal egg count measurements but identification of genetic indicators of resistance will provide a more efficient method of selection. Current quantitative trait loci for nematode resistance include the MHC genes, interferon gamma gene, IgE gene and microsatellites on chromosome 1, 5 and 6. This paper reviews the current alternatives to anthelmintics to control infection, with an emphasis on breeding for host resistance and identification of genetic indicators of resistance.

Keywords

sheepgastrointestinal nematodesQTLanthelmintics
Type
Research Article
Information
Animal Health Research Reviews , Volume 6 , Issue 2 , December 2005 , pp. 159 - 171
Copyright
Copyright © CAB International 2005

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