title: Bovine spongiform encephalopathy: epidemiological studies on the origin.
abstract: The results of further epidemiological studies of bovine spongiform encephalopathy (BSE) support the previous findings that the onset of exposure of the cattle population to a scrapie-like agent, sufficient to result in clinical disease, occurred in 1981/82. The onset of this exposure was related to the cessation, in all but two rendering plants, of the hydrocarbon solvent extraction of fat from meat and bone meal. A further possible explanation, related to the geographical variation in the reprocessing of greaves to produce meat and bone meal, was identified for the geographical variation in the incidence of BSE.
authors.affiliation: Epidemiology Unit, Central Veterinary Laboratory, New Haw, Weybridge, Surrey.
authors.forename: J W
authors.initials: JW
authors.lastname: Wilesmith
authors.forename: J B
authors.initials: JB
authors.lastname: Ryan
authors.forename: M J
authors.initials: MJ
authors.lastname: Atkinson
mesh_terms: D000367:Age Factors; D000818:Animals; D001688:Biological Products; D001927:Brain Diseases / Q000453:epidemiology / Q000209:etiology / Q000662:veterinary*; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000209:etiology; D005223:Fats / Q000032:analysis*; D008460:Meat / Q000032:analysis*; D008903:Minerals / Q000032:analysis*; D012897:Slow Virus Diseases / Q000453:epidemiology / Q000209:etiology / Q000662:veterinary*
chemical_list: D001688:Biological Products; D005223:Fats; D008903:Minerals; C027762:bone meal