Equine locomotion: 2. The analysis of coordination between limbs of trotting standardbreds.

A high-speed cinematographic analysis of interlimb time and linear gait characteristics was carried out at racing speed (12.0 m/sec; 1:23.6 min/km) in 30 clinically sound Standard-bred trotters. In respect of the whole group of horses the racing trot was found to be a very regular and symmetric gait. The variation coefficient between different horses ranged from 8 to 21 per cent depending on the particular characteristic being investigated. The variations recorded in individual animals were about 60 per cent less than those found for the whole group. The most stable characteristics were the duration and length of the step. Some horses exhibited striking gait asymmetries and the possible causes are considered. It is also observed that some trotters adopt a transition of gait that cannot be classified as a trot.