title: The Bolivian "Altiplano" and "Valle" sheep are two different peripatric breeds.
abstract: Forty-nine sheep belonged to the Andean Altiplano region ("Altiplano") and 30 in the lowland regions of Bolivia ("Valle"), aged 1 to 4 years, were wool sampled to determine the extent of difference between these local breeds. Fibre length and the percentage of each type of fibre (long-thick, short-thin and kemp), yield and fibre diameter were measured. There was a highly significant difference between the two sheep populations that were not clearly separated in the first two principal component of a principal components analysis (PC); the first PC explained 67.1 % and the second PC explained 26.6 % of the total variation. The variables that contributed most to the separation of the sheep populations were the percentage of long-thick and short-thin fibres in the first PC and yield in the second PC. A discriminant analysis, which was used to classify individuals with respect to their breeding, achieved an accurate classification rate of 84.2 %. Thus, the Altiplano and Valle sheep must be viewed as two closely peripatric breeds rather than different "ecotypes", as more than 80 % could be correctly assigned to one of the breeds; however, the differences are based on composition of long-thick and short-thin fibres and yield after alcohol scouring.
authors.affiliation: Department of Animal Production, University of Lleida, Catalunya, Spain, peremiquelp@prodan.udl.cat.
authors.forename: Pere M
authors.initials: PM
authors.lastname: Parés-Casanova
authors.forename: Raúl
authors.initials: R
authors.lastname: Pérezgrovas Garza
mesh_terms: D000818:Animals; D001838:Bolivia; D001947:Breeding; D016002:Discriminant Analysis; D025341:Principal Component Analysis; D012756:Sheep / Q000145:classification / Q000235:genetics*; D014935:Wool / Q000592:standards