title: Serologic survey of prevalence of ovine progressive pneumonia in Idaho range sheep.
abstract: Blood samples from 2,310 mature sheep in 3 Idaho range flocks were examined by agar gel immunodiffusion to determine the prevalence of ovine progressive pneumonia. The prevalence ranged from 58% for all ages combined in one flock to 90% of cull ewes in another flock. Age-specific prevalence rates increased from 16% in yearlings to 83% in ewes greater than or equal to 7 years old. Rambouillet sheep had a significantly (P less than 0.01) lower prevalence than sheep of 5 other breeds, whereas one-half Finnsheep crosses had a significantly (P less than 0.01) higher prevalence than sheep of other breeds. Within breed and age, there was no significant difference in reproductive performance between seropositive and seronegative ewes.
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis; D007061:Idaho; D005779:Immunodiffusion; D011021:Pneumonia, Progressive Interstitial, of Sheep / Q000453:epidemiology* / Q000276:immunology; D012756:Sheep; D014790:Visna-maedi virus / Q000276:immunology
chemical_list: D000914:Antibodies, Viral