Genetic Parameters of Foal Inspection Scores in the International Sporthorse Registry and Oldenburg Registry North America

Foal scores from the International Sporthorse Registry and Oldenburg Registry North America were used for statistical and genetic analysis. Scored traits include type and conformation (TC), athletic ability of movement (AM), overall development as related to age (OD), and total score (TS) calculated as a weighted average of TC, AM, and OD. Premium status (PS) was analyzed as a binary trait. Preliminary statistical analysis determined significant fixed effects of sex, year of birth, dam breed, and inspection period. Offspring of stallions with only one offspring in the dataset and non-warmblood sires were deleted. Non-warmblood or non-Thoroughbred dams were also removed. Variance components were estimated using ASReml methodology to obtain genetic parameters. Traits were moderately to highly heritable with heritabilities of 0.45, 0.47, 0.49, and 0.55 for TC, AM, OD, and TS, respectively. PS had a heritability of 0.32 on a binary scale and 0.51 when transformed to the normal scale. Genetic correlations between TC, AM, OD, and TS were all high and favorable, ranging from 0.80 to 0.99. Genetic correlations with PS were inestimable. Foal inspection scores are heritable and should respond to selection. Selection for improvement in one trait should result in improvement in all traits. If genetic parameters can be correlated to data obtained in older horses, incorporating foal scores in selection decisions could improve warmblood breeding programs. Utilizing foal inspection scores should be beneficial to breeding objectives of the International Sporthorse Registry and Oldenburg Registry North America.