Analysis of video-recorded images to determine linear and angular dimensions in the growing horse.

The research article discusses a study that developed an objective system for assessing horse growth and conformation through the analysis of video-recorded images. The system evaluates structural features by measuring angles and lengths from video images, providing a method that is more exact and consistent than traditional subjective standards.

Objective of the Study

• The study aimed to develop and assess a new system that offers an objective evaluation of growth and conformation in horses.
• Unlike conventional subjective assessment methods used by breeders and trainers, this system leverages image analysis technology to ensure accuracy and consistency.

Methodology

• A studio crush was set up to capture video images of horses of varying sizes. Bone protuberances identified through palpation were marked with white paper stickers.
• The pixel coordinates of calibration marks, bone markers, and points on horse outlines were digitised from captured images and then corrected to account for aspect ratio and ‘fish-eye’ lens effects.
• Linear and angular dimensions were generated from the corrected coordinates, which were valuable for comparing horses for conformation and experimental reasons.

Results

• The precision of determining linear and angular dimensions through this method was explored by systematically examining variance for isolated procedure steps.
• Angles of the front limbs viewed from the front were determined with a standard deviation of 2-5 degrees, and the impacts of viewing angle were statistically noticeable.
• The height of the rump and wither were identified with precision closely related to the limitations faced in locating a point on a screen. This was greater for markers applied to the skin than for points on the edge of the image.
• Notably, parameters derived from markers applied to the skin were more variable, as movement could affect their relationship to bone position. They still provided a method for objectively determining various aspects of size and conformation for multiple horses during growth.
• The precision was significant enough to detect statistically relatively small effects on calculated parameters of camera height position.

Implications

• The study presents a new, objective approach to measure and study growth and conformation in horses, which could be a valuable tool for both the scientific community and the horse industry.
• This method moves from subjective evaluations to a precise, data-driven analysis, enabling more accurate and consistent results.