They are among the equine elite, competing on the world stage at the highest levels of dressage. But how comfortable are these highly trained athletes in their work?
A just-published study focused attention on elite dressage horses competing in World Cup Grand Prix qualifying competitions or finals, applying the Ridden Horse Pain Ethogram (RHpE).
Leading lameness researcher Sue Dyson led research about three years ago that led to the development of the RHpE, and is extensively trained in its use.
It comprises 24 behaviours, each with strict definitions, that occur more frequently in a horse with musculoskeletal discomfort compared with a non-lame horse.
They include the likes of mouth opening with separation of the teeth for at least 10 seconds, repeated head tilting, persistent tail swishing, an intense stare for five or more seconds, spooking, bucking, rearing, tail clamping, repeated tongue exposure, and putting the ears back for more than five seconds.
The presence of at least 8 of the 24 behaviours is considered a reliable indicator of the presence of an underlying musculoskeletal problem. The higher the tally, the greater the likelihood that the horse has musculoskeletal discomfort which may compromise performance.
It has previously been shown that the most frequent score in non-lame horses is 2 out of 24.
Dyson and her colleague Danica Pollard, in research just published in the journal Animals, hypothesised that the elite dressage horses at the centre of their study should have a low incidence of musculoskeletal pain. Thus, their RHpE scores should be consistently less 8.
Dyson applied the RHpE to video recordings of 147 competitors at nine venues.
The median RHpE score for all competitors was 3 out of 24, with the highest score among the horses being 7.
“This study provided evidence that, at elite level, most of the Grand Prix dressage horses studied were comfortable in the majority of their work, based on the RHpE scores,” Dyson and Pollard reported.
“However, some horses showed episodic discomfort, and identification of the cause may enhance equine welfare and performance.”
There was a moderate negative correlation between the RHpE score and the judges’ score — that is, there was a moderate tendency for horses with higher RHpE scores to receive lower scores from the judges.
The pair said their research found that these horses frequency worked with the front of their head 10 degrees or more behind a vertical position for 10 or more seconds. They were also frequently seen to have their mouths open with the separation of the teeth for 10 or more seconds. Repeated tail swishing was also common.
Dyson and Pollard concluded that although the median RHpE score was low, there was evidence that some horses were showing signs consistent with occasional discomfort.
“There are many potential reasons including primary musculoskeletal pain, especially associated with biomechanically more demanding movements; pain induced by the tack; alterations in the rider’s weight distribution; and the manner in which cues were applied.”
The cause in any particular horse could be determined only by careful clinical assessment by suitably qualified professionals, they said.
“However, this requires that the presence of a potential problem is recognised by the team producing the horse and that appropriate advice is sought.
“This approach may result in both improved performance and enhanced equine welfare.”
The pair said further investigation of the influence of a double bridle compared with a snaffle bridle on head position and mouth opening was merited.
Dyson, S.; Pollard, D. Application of the Ridden Horse Pain Ethogram to Elite Dressage Horses Competing in World Cup Grand Prix Competitions. Animals 2021, 11, 1187. https://doi.org/10.3390/ani11051187