title: Prevalence and seasonality of bulk milk antibodies against Dictyocaulus viviparus and Ostertagia ostertagi in Irish pasture-based dairy herds.
abstract: Infections with Dictyocaulus viviparus and Ostertagia ostertagi nematode parasites are of importance to bovine health and production in temperate areas across the world. Losses due to these parasites in dairy herds can be considerable due to decreased milk productivity and fertility. However, information on current epidemiological patterns in Irish dairy herds is limited. Bulk milk samples were collected from a total of 319 dairy farms across the Republic of Ireland. The D. viviparus samples were tested with an ELISA based on recombinant major sperm protein, while the O. ostertagi samples were tested with an ELISA based on crude saline extract, whole worm O. ostertagi antigen. Management data were collected from the farms using a questionnaire. Logistic regression was used to find significant associations between the presence of antibodies against D. viviparus and O. ostertagi and management factors. The overall prevalence of D. viviparus infection was 62.8%, while over 98% of herds had antibodies to O. ostertagi at the specified cut-off. Both D. viviparus and O. ostertagi antibodies were highest in November, which could be explained by the accumulated uptake of larvae through the grazing season. In herds of farmers that dosed their in-calf heifers with anthelmintics were significantly more likely to be positive for antibodies against D. viviparus infection. This study highlights that both D. viviparus and O. ostertagi infections are widespread in dairy herds in Ireland throughout the grazing season.
authors.affiliation: Animal and Bioscience Research Department, Animal & Grassland Research and Innovation Centre, Teagasc, Moorepark, Fermoy, Co. Cork, Ireland.
authors.forename: Yris
authors.initials: Y
authors.lastname: Bloemhoff
authors.affiliation: Merial, 29 Avenue Tony Garnier, 69007 Lyon, France.
authors.forename: Andrew
authors.initials: A
authors.lastname: Forbes
authors.affiliation: Animal and Grassland Research and Innovation Centre, Teagasc, Athenry, Co. Galway, Ireland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Good
authors.affiliation: School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, United Kingdom.
authors.forename: Eric
authors.initials: E
authors.lastname: Morgan
authors.affiliation: School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.
authors.forename: Grace
authors.initials: G
authors.lastname: Mulcahy
authors.affiliation: Institute for Parasitology, University of Veterinary Medicine Hannover, Buenteweg 17, 30559 Hannover, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Strube
authors.affiliation: Animal and Bioscience Research Department, Animal & Grassland Research and Innovation Centre, Teagasc, Moorepark, Fermoy, Co. Cork, Ireland. Electronic address: riona.sayers@teagasc.ie.
authors.forename: Ríona
authors.initials: R
authors.lastname: Sayers
mesh_terms: D000818:Animals; D000909:Antibodies, Helminth / Q000737:chemistry*; D002417:Cattle; D002418:Cattle Diseases / Q000469:parasitology*; D004021:Dictyocaulus / Q000276:immunology*; D004022:Dictyocaulus Infections / Q000453:epidemiology / Q000469:parasitology; D005260:Female; D007494:Ireland / Q000453:epidemiology; D008892:Milk / Q000737:chemistry*; D010028:Ostertagia / Q000276:immunology*; D010029:Ostertagiasis / Q000453:epidemiology / Q000662:veterinary; D012621:Seasons
chemical_list: D000909:Antibodies, Helminth
keywords: Bulk milk; Dairy herds; Dictyocaulus viviparus; Ireland; Ostertagia ostertagi