title: Frequency of eprinomectin resistance in gastrointestinal nematodes of goats in canton Berne, Switzerland.
abstract: Eprinomectin (EPN) is a member of the avermectin class of compounds and the only anthelmintic registered for goats in Switzerland with a zero milk withdrawal period. The aim of the present study was to identify the actual efficacy of EPN in an area with a higher density of goat enterprises. Forty-three randomly chosen farms from canton Berne were investigated. At least eight goats were investigated on every farm. Conditions for inclusion in the study were the absence of anthelmintic treatment during the previous six weeks and a pooled faecal sample showing a mean faecal egg count (FEC) higher than 600 epg faeces. Pre- and 14-16 days post-treatment samples were individually collected directly from the rectum. Animals were treated with the recommended dose of EPN (1 mg/kg body weight) after taking the pre-treatment samples. Efficacy of EPN was tested with the faecal egg count reduction test (FECRT) and faecal cultures were performed on every farm from pooled faeces samples before and after treatment. Additionally the farmers completed a questionnaire. None of the gastrointestinal nematode populations of the 43 investigated farms were susceptible to EPN at the required level. The mean egg count reduction was 40%. None of the typical risk factors, such as production type, stocking rate, animal traffic and quarantine measures showed an association with the level of eprinomectin resistance. It can be concluded with 80% certainty that the prevalence of EPN resistance on goat farms is at least 95% in canton Berne.
authors.affiliation: Ambulatory Clinic and Herd Management Unit, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland; Institute of Parasitology, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 266a, 8057 Zurich, Switzerland.
authors.forename: Sarah
authors.initials: S
authors.lastname: Murri
authors.affiliation: Clinic for Ruminants with Ambulatory and Herd Health Services at the Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University Munich, Sonnenstrasse 16, 85764 Oberschleissheim, Germany.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Knubben-Schweizer
authors.affiliation: Section of Epidemiology, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 270, 8057 Zurich, Switzerland.
authors.forename: Paul
authors.initials: P
authors.lastname: Torgerson
authors.affiliation: Institute of Parasitology, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 266a, 8057 Zurich, Switzerland. Electronic address: hubertus.hertzberg@access.uzh.ch.
authors.forename: Hubertus
authors.initials: H
authors.lastname: Hertzberg
mesh_terms: D000818:Animals; D004351:Drug Resistance; D041981:Gastrointestinal Tract / Q000469:parasitology*; D015511:Goat Diseases / Q000188:drug therapy / Q000469:parasitology*; D006041:Goats; D007559:Ivermectin / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D009348:Nematoda / Q000187:drug effects*; D009349:Nematode Infections / Q000188:drug therapy / Q000469:parasitology / Q000662:veterinary*; D010270:Parasite Egg Count; D012307:Risk Factors; D011795:Surveys and Questionnaires; D013557:Switzerland
chemical_list: D007559:Ivermectin; C101434:eprinomectin
keywords: Anthelmintic resistance; Eprinomectin; Gastrointestinal nematodes; Goats; Switzerland