title: Herd risk factors associated with sero-prevalence of Maedi-Visna in the Manitoba sheep population.
abstract: Disease associated with Maedi-Visna infection results in substantial economic losses in affected sheep producing areas of the world. A survey was conducted to estimate herd and individual seroprevalence in the province of Manitoba and evaluate risk factors for seropositive herds. Of 2207 sheep sampled from 77 selected sheep flocks, the animal level seroprevalence was 2.47% and herd level seroprevalence was 25.10%. The herd-level factors of presence of clinical skin disease, herd size of > 70, history of musculoskeletal/lameness abnormalities, and the purchase of new stock (> 50) in the last 1 to 5 y, showed significant associations with seropositive herd status. The study documented a remarkable stability of low seroprevalence in the province over a 20-year period in the absence of a systematic disease control program.
authors.affiliation: Office of the Chief Veterinarian, Manitoba Agriculture Food and Rural Initiatives, 545 University Crescent, Winnipeg, Manitoba R3T 5S6.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Shuaib
authors.forename: Chris
authors.initials: C
authors.lastname: Green
authors.forename: Mamoon
authors.initials: M
authors.lastname: Rashid
authors.forename: Glen
authors.initials: G
authors.lastname: Duizer
authors.forename: Terry L
authors.initials: TL
authors.lastname: Whiting
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D005260:Female; D008297:Male; D008350:Manitoba / Q000453:epidemiology; D011021:Pneumonia, Progressive Interstitial, of Sheep / Q000453:epidemiology*; D011156:Population Density; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D012756:Sheep; D014790:Visna-maedi virus / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral