Farm animals

Sherwin, CM

doi:10.1007/978-94-011-0699-3_7

Cited by 1 publication

(1 citation statement)

References 80 publications

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“…Technological advances and the value of video-imaging analysis are obvious, for example, in studies of horse motion analysis (Clayton 1991), and animal ecology and behaviour (Altmann 1974;Sherwin 1993;Wratten 1993), where advantages relevant to measuring objectively the dimensions and shape of horses include the ability to: replay observations many times; form an accurate permanent record of observations;. eliminate problems of observer fatigue; and eliminate the difficulties of making many detailed measurements in real time.…”

Section: Introductionmentioning

confidence: 99%

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

Hunt

Thomas

Stiefel

1999

Equine Veterinary Journal

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Summary Studies of growth and conformation require statistical methods that are not applicable to subjective conformation standards used by breeders and trainers. A new system was developed to provide an objective approach for both science and industry, based on analysis of video images to measure aspects of conformation that were represented by angles or lengths. A studio crush was developed in which video images of horses of different sizes were taken after bone protuberances, located by palpation, were marked with white paper stickers. Screen pixel coordinates of calibration marks, bone markers and points on horse outlines were digitised from captured images and corrected for aspect ratio and ‘fish‐eye’ lens effects. Calculations from the corrected coordinates produced linear dimensions and angular dimensions useful for comparison of horses for conformation and experimental purposes. The precision achieved by the method in determining linear and angular dimensions was examined through systematically determining variance for isolated steps of the procedure. Angles of the front limbs viewed from in front were determined with a standard deviation of 2–5 degrees and effects of viewing angle were detectable statistically. The height of the rump and wither were determined with precision closely related to the limitations encountered in locating a point on a screen, which was greater for markers applied to the skin than for points at the edge of the image. Parameters determined from markers applied to the skin were, however, more variable (because their relation to bone position was affected by movement), but still provided a means by which a number of aspects of size and conformation can be determined objectively for many horses during growth. Sufficient precision was achieved to detect statistically relatively small effects on calculated parameters of camera height position.

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Section: Introductionmentioning

confidence: 99%