Genetic diversity among some cattle breeds in the Alpine area

Abstract

Seven autochthonous Italian cattle breeds bred in the alpine area (Aosta Black Pied, Aosta Red Pied, Aosta Chestnut, Oropa Red Pied, Grey Alpine, Rendena and Burlina) were investigated in order to characterise their genetic structure and to study their phylogenetic origin. Two cattle breeds from Germany (Original German Brown and Holstein) and four from Switzerland (Simmental, Herens, Evolene and Brown Swiss) were included in the study in order to determine the genetic diversity existing among Italian local breeds, similar breeds bred on the other side of the Alps and in the well known Holstein.Seventeen microsatellites, of the internationally accepted panel for the study of cattle biodiversity, were used for the analysis.Microsatellites were highly polymorphic with a mean number of 5,5 alleles (ranging from 2 to 12 per locus). For each locus, allelic frequencies, heterozygosity (H) and the Polymorphism Information Content (PIC) were computed. The genetic equilibrium according to Hardy–Weinberg was calculated for each population and for each locus. Allele frequencies were used to estimate genetic distances and to draw a phylogenetic tree. The two closest breeds were Aosta Red Pied and Aosta Black Pied, while the two genetically most different were Holstein and Aosta Chestnut. Aosta valley breeds, Evolene and Herens constituted a tight cluster in the phylogenetic consensus tree. Principal component analysis showed a similar pattern for all the alpine breeds, while Holstein and Original German Brown were far away. The genetic differences among breeds were in accordance with their geographical and historical origins.