Study Title: "Weight Changes in Endurance Horses" |
Study Team
Leah C. Gray, DVM, Veterinary Medical Teaching Hospital;
Gary P. Carlson, DVM, PhD, Department of Medicine and Epidemiology; Stephen
G. Leonard, DVM, Grantline Veterinary Hospital. |
Purpose of Study
The purpose of this study was to determine weight
changes in endurance horses during a one-day 100-mile endurance ride (1999
Tevis Cup Ride). |
Method
A portable digital load cell weight scale (TRU-TEST AG500
Series Agriculture, Version 3.2, Tru-Test Inc., San Antonio, TX) was used.
Riders volunteered to have their horses weighed without tack at three
veterinary checkpoints: start at Robie Equestrian Park (mile 0), Foresthill
(mile 69), and the finish at Stadium (mile 100). All weights were taken
immediately upon entry to the checkpoint prior to access to food or water.
Official race times, average temperature, and average humidity were
recorded. |
Findings
Of 224 starters, 197 horses were weighed at Robie, 35 at
Foresthill, and 68 at the Stadium. A total of 114 (50.9%) horses finished the
race. Horses that did not finish were eliminated for various reasons: lameness,
metabolic causes, overtime, or rider option. Nine of the Top 10 finishers were
weighed again the morning after the race, during recovery . The average weight
loss from start to finish for all finishers was -22.7 ± 9.9 kg (-5.5
± 2.3% BW). The average weight loss for the Top 10, -21.1 ± 13.1
kg (-5.0 ± 2.9 % BW). The morning after the ride these horses had gained
+ 5.6 ± 6.1 kg (+ 1.4 ± 1.5 % BW) with a residual deficit of
-15.5 ± 9.1 kg (-3.7 ± 2.0 % BW). |
Conclusions
There was a large variation in initial body weight (range
329.1 - 506.8 kg), The 1999 Tevis Cup ride was over the usual challanging
terrain but in moderate weather conditions. Despite these mild conditions, the
average weight loss was > 5 % and some normal horse had weight loss > 10%
at the end of the ride . It was expected that the top competitors ridden at a
faster pace would have had greater weight loss. However, weight losses were
similar in the later finishers. The pattern of weight loss experienced at
Foresthill, 2/3 into the ride, carried through to the stadium. Dehydration is a
common feature even in normal horses that complete the ride. Rehydration may
require more than 12 hours following an endurance ride. |
