+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Anthelmintic resistance in Northern Ireland (I): prevalence of resistance in ovine gastrointestinal nematodes, as determined through faecal egg count reduction testing



Anthelmintic resistance in Northern Ireland (I): prevalence of resistance in ovine gastrointestinal nematodes, as determined through faecal egg count reduction testing



Veterinary Parasitology 195(1-2): 122-130



The prevalence of anthelmintic resistance in Northern Ireland sheep flocks was evaluated between July and October 2011. Sampling kits were sent to 172 flock owners and returns were received from 91. Within this survey population, 27 flock owners used benzimidazole products, 10 used levamisole products, 15 used avermectin products, 26 used milbemycin products and 4 flock owners used the amino acetonitrile derivative, Monepantel. The remaining 9 flock owners used combination drenches (broad spectrum wormer plus fasciolicide). However, 15 sets of samples were ineligible for faecal egg count reduction testing due to either too low an egg count or insufficient faecal volume. Treatment efficacy below 95%, indicating significant resistance, was detected in 81% (n=24) of flocks tested for benzimidazole resistance; in 14% (n=1) of flocks tested for levamisole resistance; and in 50% (n=7) and 62% (n=13) of flocks tested for avermectin and milbemycin resistance, respectively. Monepantel resistance was absent in all (n=3) flocks tested. Combination products (broad spectrum nematocide plus flukicide) containing levamisole were entirely effective, while treatment efficacy below 95% was detected in 60% (n=3) of flocks where the nematocide in the combination product was a benzimidazole. Where parasite identification based on coproculture was completed, Trichostrongylus was the dominant genus detected in all cases post-treatment, indicating the occurrence of anthelmintic-resistant Trichostrongylus spp. populations. Benzimidazole efficacy was highest in treating Trichostrongylus spp. (51%) and lowest when treating Teladorsagia spp. Levamisole was 100% effective in treating Cooperia, but ineffective (0%) in treating Trichostrongylus spp. Avermectin efficacy was highest when treating Haemonchus contortus (100%) and Teladorsagia spp. (73%), with a marginally lower efficacy against Trichostrongylus spp. (71%). Moxidectin efficacy was 33% against Trichostrongylus spp., 68% against Teladorsagia spp., 97% against Cooperia spp. and 100% against Haemonchus contortus infections.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 036912999

Download citation: RISBibTeXText

PMID: 23398988

DOI: 10.1016/j.vetpar.2013.01.006


Related references

Prevalence and severity of anthelmintic resistance in ovine gastrointestinal nematodes in Australia (2009-2012). Australian Veterinary Journal 92(12): 464-471, 2015

Potential for misinterpretation of the faecal egg count reduction test for levamisole resistance in gastrointestinal nematodes of sheep. Veterinary Parasitology 62(3-4): 267-273, 1996

Criteria for diagnosing anthelmintic resistance by the faecal egg count reduction test. New Zealand Veterinary Journal 42(4): 153-154, 1994

Anthelmintic resistance in ovine gastrointestinal nematodes in inland southern Queensland. Australian Veterinary Journal 92(11): 415-420, 2015

Detection of anthelmintic resistance in sheep and goat against fenbendazole by faecal egg count reduction test. Journal of Parasitic Diseases 41(2): 463-466, 2017

Faecal egg count reduction percentage calculations to detect anthelmintic resistance in Oesophagostomum spp. in pigs. Veterinary Parasitology 68(1/2): 127-142, 1997

Potential limitations of the undifferentiated faecal egg count reduction test for the detection of anthelmintic resistance in sheep. New Zealand Veterinary Journal 44(2): 73-75, 1996

Survey of anthelmintic resistance on Danish horse farms, using 5 different methods of calculating faecal egg count reduction. Equine Veterinary Journal 30(4): 289-293, 1998

Further potential limitations of the undifferentiated faecal egg count reduction test for the detection of anthelmintic resistance in sheep. New Zealand Veterinary Journal 45(6): 244-246, 2005

The detection of anthelmintic resistance by the faecal egg count reduction test: an examination of some of the factors affecting performance and interpretation. New Zealand Veterinary Journal 38(4): 142-147, 1990

A comparison of in vitro tests and a faecal egg count reduction test in detecting anthelmintic resistance in horse strongyles. Veterinary Parasitology 85(1): 49-59, 1999

Improving the detection of anthelmintic resistance: evaluation of faecal egg count reduction test procedures suitable for farm routines. Veterinary Parasitology 196(3-4): 438-452, 2014

Prevalence of anthelmintic resistance in gastrointestinal nematodes of sheep and goats in Norway. Parasitology Research 111(1): 185-193, 2012

Update on the prevalence of anthelmintic resistance in gastrointestinal nematodes of sheep in New Zealand. New Zealand Veterinary Journal 58(3): 172-173, 2010

Evaluation of prevalence and clinical implications of anthelmintic resistance in gastrointestinal nematodes in goats. Journal of the American Veterinary Medical Association 223(4): 495-500, 2003