Comparison between Factor Analysis from a Phenotypic and Genetic Correlation Matrix Using Linear Type Traits of Holstein Dairy Cows

Abstract

Data on 18 linear type scores and production data for 43,428 records by 228 sires were used to compare two different factor-analyses procedures. Using a genetic correlation matrix to obtain a genetic factor matrix showed that the number of derived factors could be reduced to seven genetic factors vs. eight phenotypic factors. Genetic factors provided a good summary of the data and accounted for 79.3% of the total variation vs. 69.1% expressed by eight phenotypic factors. A comparison between the use of a genetic and phenotypic multiple regression analysis showed some difference for the basic rank of factor influence on production and herdlife. © 1988, American Dairy Science Association. All rights reserved.