Estimation of dispersion parameters for linear type traits in the Haflinger horses

Abstract

The covariance components for exterior traits were estimated on Haflinger horses in Slovenia. There were 3371 data included in the database. Data from 600 animals (15 stallions and 585 mares) with known pedigree were analysed. For each horse, at most ten traits were scored and nine traits were measured. The fixed part of the model included only the year when horse was scored or measured and animal was treated as random effect. Genetic and environmental parameters for exterior traits were estimated by the restricted maximum likelihood method (REML) as implemented in the program package VCE. To make matrices positive definite we used a statistic method commonly known as ’bending’. Heritabilities for the scored traits were estimated between 0.40 for front body part and 0.78 for the breed type. For measured traits the heritabilities were between 0.20 for chest depth and 0.62 for withers height (measuring stick). Genetic corelations were in most cases positive. The highest genetic corelation for scored traits was 0.92 between total score and rear body part. There was no corelation betwen breed type and front legs. Genetic corelations for measured traits were from 0.38 between body lenght and chest size to 0.95 betwen withers hight measured with stick and measured with tape.