Page 998 - Adams and Stashak's Lameness in Horses, 7th Edition
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964 Chapter 9
THE STANDARDBRED RACEHORSE
VetBooks.ir KimbeRly Johnston and FRanK a. niCKels
DESCRIPTION OF THE SPORT conformational faults predispose to interference or
lameness problems. Toeing out is undesirable in the
The name Standardbred originated in 1879 in the front limbs, especially when accompanied by a base‐
United States with registration of horses capable of trot narrow stance. This conformation affects the flight of
ting a mile within a standard time of 2:30 minutes. Now the hoof and can cause interference. Toeing in causes less
the Standardbred is a distinct breed with foals eligible interference but results in an inefficient gait and increases
for registration if both sire and dam are registered the strain on the medial side of the limb, leading to car
Standardbreds, regardless of racing performance. pal pain and the development of splints. Horses that are
Today’s Standardbreds currently race much faster, with offset or back at the knees are at risk of carpal chips and
pacers completing a mile in less than 1:50 minutes and slab factures. Sickle hocks used to be common in pacers
trotters only a few seconds slower. Racing is done on an and were even selected for, but sharp angulation of the
oval track, usually a mile in length, and horses pull light hindlimb predisposes to curb and hock arthritis. In con
weight carts with a single driver. In the United States trast, many trotters are cow hocked, but unless severe,
racing is counterclockwise and commences from a mov this conformation may be advantageous because it
ing start with horses at their post position behind a vehi allows a passing gait in which the imprint of the hindlimb
cle with a collapsible partition. Standardbreds race at falls outside the imprint of the forelimb, providing a
either the trot or the pace. In the United States, pacers longer stride.
outnumber trotters 4:1, while in Europe and Australia, Standardbreds are broken to harness as yearlings and
races are held at the trot only. A horse may have the abil train for 7–9 months before racing as 2‐year‐olds.
ity to perform both gaits, but Standardbreds tend to race Horses are jogged at a slow trot/pace for several miles
at only one gait for their entire career. In general, pacers daily to gain fitness and stamina. Jogging is done “the
seem to tolerate lameness better than trotters due to the wrong way” (clockwise) around the track, and a few
perpetual swinging motion of the pace itself. times a week, a horse is turned to work “the right way”
The Standardbred resembles the Thoroughbred; for short bursts of speed training. During peak season,
however, it is longer and does not stand as tall, averag Standardbreds may race as often as once a week. This
ing between 14.2 and 16 hands. Adequate body length is pounding on hard tracks for many miles and the fact
essential for a long stride and to allow free movement of that Standardbreds race and train in different directions
the limbs without interference. Conformation plays a makes them prone to repetitive stress and maladaptive
pivotal role in the success of the racehorse, and many bone injuries (Figure 9.15).
Figure 9.15. Although the pace is a
natural gait, horses often wear hobbles to
help maintain the gait while racing. This
equipment commonly causes hairless
areas on the legs, making a Standardbred
pacer readily identifiable.
