Diversity and comparison of wool parameters in 31 different American and European ovine breeds

Abstract

A study was designed with the aim of establishing phenotypic relationships between certain American and European autochthonous sheep breeds based on wool parameters. Data were collected from 1,143 animals from 31 sheep breeds or varieties. Nine quantitative wool characteristics – length and amount of long, short and kemp fibres, mean fibre diameter and fibres with diameter > 30 μ, and percentage after degreasing with alcohol - were investigated. A principal component analysis (PCA) was carried out with the aim of obtaining the variables exhibiting a pattern of jointly contributing to the total variation. To present data structure and relationship among population accessions, a cluster analysis and a principal coordinates analysis of all the data were conducted. For all analyses, the correlation matrix was utilised. Percentage of fibres and fineness appear as the most useful grouping criteria. The resulting dendrogram showed a ‘short coarse wool sheep’, a ‘medium fine wool sheep’ (with different percentages of short fibres that allow them to be divided into three subgroups) and a ‘long medium wool sheep’. No ‘short fine wool sheep’ appeared. Although no phylogenetic information is generated, the results seem to establish different, but more concise groups than those traditionally considered: Merino, Entrefino, Churro and Iberian stock.