Evaluation of a Novel System for Linear Conformation, Gait, and Personality Trait Scoring and Automatic Ranking of Horses at Breed Shows: A Pilot Study in American Quarter Horses.

The research focuses on comparing a traditional horse judging system using subjective grades and an innovative system utilizing linear scoring powered by a Breed Show App. The study showcased that the new application could potentially yield a more detailed assessment of horses, particularly in relation to complex traits like personality, therefore improving differentiation between horses.

Methodology

• In the study, the research team looked into a total of 1,909 American Quarter horses which were judged at regular breed shows using either Traditional (T) (n = 883), Linear Scoring (LS) (n = 1,026), or both systems (n = 17).
• Beyond this, traits suitable for use in personality evaluation using LS were chosen (n = 559 horses).
• For statistical analysis, both Mixed-Model Analysis and Pearson correlations were employed to determine agreement between the two systems and to pinpoint highly correlated personality traits.
• The LS assessed the horse’s quality in relation to the total breeding aim using weighting factors for 57 individual traits commonly considered in T.
• The results from both systems were represented as a total grade percentage.

Key Findings

• The research found that the average total grade was higher in T (83.3 ± 0.2%) than LS (81.7 ± 0.3, P < .0001).
• However, overall grades displayed a wider range with LS, indicative of it better reflecting phenotypic variance and improving comparability between different horses, without having an impact on the overall horse ranking (r = 0.95, P < .00001).
• Despite similar rankings, the LS system revealed a more detailed scoring, allowing for better differentiation, especially in complex traits like personality.
• Most personality traits deviated from a normal distribution (Kolmogorov-Smirnov: P < .01), potentially signaling that genetic or phenotypic preselection occurred among the participating horses.
• There was also an interesting finding that foals judged as more “bright” tended to keep a larger distance from their dam (r = 0.4) and displayed more exploration of the environment (r = 0.2, P < .01).

Implications

• The study proved that the Breed Show App, an application that utilizes linear scoring (LS), appeared as a potential improvement over traditional methods of horse judging.
• The LS system does not just provide similar ranking results as the traditional system, but offers more detailed assessments that help to differentiate between horses, especially with respect to complex traits like personality.
• The findings offer a meaningful contribution to improving the quantitative analysis of horse traits and behavior, ensuring judgements are more comprehensive and reliable, and giving a more solid foundation for decision-making in horse selection and breeding aims.