Analysis of new temperament traits to better understand the trait spirit assessed in breeding field tests for Icelandic horses

This study investigated different aspects of the trait spirit that is routinely recorded in breeding field tests (BFTs) for Icelandic horses. Genetic parameters were estimated for spirit and six newly introduced temperament suppleness traits assessed by judges and riders in Icelandic BFTs, and for everyday life temperament traits assessed by owners of breeding horses in 2014 and 2015. The findings suggested moderate heritability for some temperament traits assessed by riders in BFTs and showed that the assessment method needs to be improved in order for judges to discern the variation in these traits. Furthermore, according to estimated correlations the score for spirit described only part of the general temperament of the horse, where aspects of general nerve strength was not well covered. Nevertheless, no clearly unfavourable correlations with spirit were found and the majority of horse owners surveyed in this study were satisfied with the assessment for spirit.