The use of foal and studbook traits in the breeding programmes of Finnhorse and Standardbred trotters.

The research study analyzes the connection between body measurements and various characteristics scored at birth and adulthood of Finnhorse and Standardbred trotters, suggesting that early selection for body conformation traits may be beneficial for breeding programmes.

Objective of the Study

• The aim of this research was to ascertain genetic correlations between body measurements and subjectively scored traits in foals and studbook horses of two breeds, Finnhorses and Standardbred trotters. This was intended to understand the efficacy of early selection of traits for breeding programs.

Data Collection and Analysis

• Data was collected from Finnish horse breeding shows. This included measurements and scores for various traits in 6529 Finnhorse foals and 6596 adult Finnhorses, as well as data on 3069 Standardbred foal trotters and 2112 adult Standardbred trotters.
• The researchers also noted the number of sires that had offspring in both the foal and adult categories. This was 203 for Finnhorses and 145 for Standardbred trotters.
• The data was analyzed using bivariate linear mixed models. The researchers estimated heritability for body measurements and subjectively scored traits in foals and adult horses using univariate models.

Findings

• The study found that heritability estimates for body measurements were high in both foals and adult horses across both breeds, with values ranging from 0.41 to 0.84.
• Heritability estimates for subjectively scored traits were generally higher for foals than adults in both breeds. These values ranged from 0.08 to 0.46 for foals, and from 0.06 to 0.21 for adult horses.
• Genetic correlations between foal and adult body measurements were highly positive, ranging from 0.74 to 0.96 in Finnhorses and from 0.79 to 0.99 in Standardbred trotters.
• There were variations in the genetic correlations for subjectively scored traits, ranging from low to highly positive in Finnhorses, and from moderately negative to highly positive in Standardbred trotters.

Implications

• The research indicates a high degree of genetic correlation between the traits observed in foals and their adult counterparts.
• Given the high heritability of both body dimensions and subjectively scored traits observed in foals and the strong correlation with adult traits, the research suggests that early selection based on these parameters could be beneficial for breeding programmes.