A survey of the trichostrongylid nematode species present on UK sheep farms and associated anthelmintic control practices

Abstract
A survey of sheep farms from across the UK was conducted to (1) establish information on farming practices and anthelmintic usage with a questionnaire posted out to farmers, and (2) to identify the trichostrongylid nematode species present on these farms. Questionnaires and samples were returned from 118 farms. Farms were categorised by location (England, Scotland, Wales and Northern Ireland), farm type (lowland, upland or hill), flock type (commercial or pedigree) and whether they ran open or closed flocks. The predominant species found were Teladorsagia circumcincta, which was present on 100% of the farms and Trichostrongylus vitrinus, which was found on approximately 95% of farms. Interestingly, Haemonchus contortus, found on approximately 50% of farms, was at significantly higher risk of being found on lowland farms compared to upland (p=0.025) or combination farms (ie farms that belong in more than one category) (p=0.034).. Data from the survey showed that only one farm did not routinely use anthelmintics, illustrating the high level of perceived risk of nematode parasites in terms of ovine disease. Determining the anthelmintic dose rate based on the weight of the heaviest animal in the flock was the most common strategy to avoid under dosing and lead to statistically significantly lower mean epg (p< 0.001) in lambs. Macrocyclic lactones were the most commonly used anthelmintic class for ewes, whilst benzimidazoles were the most widely used in lambs, further highlighting the importance of monitoring the development of resistance to these anthelmintics.
Year
2012
Category
Refereed journal
Output Tags
SG 2006-2011 WP 2.3 Control of Parasitic Diseases in Livestock