Meeting Abstract

P3.51  Tuesday, Jan. 6  Development of postural stability in horses from newborn to one month old. NAUWELAERTS, S*; MALONE, S; CLAYTON, HM; Michigan State University, East Lansing nauwelae@msu.edu

Motor control development is the sequential, continuous age-related process whereby neurological control of skilled and coordinated movements changes. The process involves changes in coordination of locomotion, development of strength, posture control, balance, and perceptual skills. Young horses are able to stand within hours after birth despite their relatively small muscle mass and immature motor control. This study analyzes the development of motor control in foals using Postural Sway Analysis (PSA). When a horse is standing stationary, gravity is counter-acted by the net ground reaction forces under each hoof. The location of the net upward force, the center of pressure (COP), can be measured using a force plate. PSA tracks movements of the COP over a period of time. In this study, PSA was performed immediately after newborn foals nursed for the first time (approximately 2 hours after birth), daily for a week, and once weekly until the foals reached one month of age. Three measurements of postural sway were used: amplitude of sway in both craniocaudal and mediolateral directions, mean sway velocities, and mean frequency after fast fourier transformation. Static balance improved rapidly. Static instability was greater in the craniocaudal direction than in the mediolateral direction, which is the opposite of what is observed in adults. Sway amplitudes decreased during the first 5-7 days after birth. Velocities and frequencies continued to decrease during the first 3 weeks post-partum. There was considerable inter-individual variation between foals that could partly be linked to differences in conformation and morphology. This study is part of a larger project that will look at development of both static and dynamic stability. We will continue to follow the foals through one year of age.