A scoring system aimed at identifying pain in horses under saddle has shown its worth in a British study, but the researchers found too many riders were on horses they did not realise were mildly lame.
The study, reported in the journal Animals, tested a Ridden Horse Pain Ethogram, made up of a list of 24 behaviours linked in previous studies to musculoskeletal pain.
The majority of the behaviours have been shown in previous research to be at least 10 times more likely to be seen in a lame horse compared with a non‐lame horse.
Researchers Sue Dyson and Danica Pollard said the presence of eight or more of the behaviours is likely to reflect musculoskeletal pain.
To further test the ethogram, first developed by Dyson and others about three years ago, the pair applied it to a sample of 60 sport horse and riding school horses in regular work. All were assumed by their owners to be working comfortably.
All horses performed a purpose‐designed 8.5-minute dressage‐style test involving the walk, trot and canter. All horses had their normal rider, of varying skill levels.
Standardised video recordings of each test were taken, which allowed the ethogram to be applied afterwards by a trained analyst.
The presence of increased back muscle tension or pain, poor saddle fit, gait abnormalities and rider skill were assessed for each horse by independent experts to compare with the ethogram results.
“There was a significant association between the Ridden Horse Pain Ethogram score and lameness,” the pair reported. “Lame horses had higher scores than non‐lame horses.”
The horse assessments revealed that 73 percent of the horses had low-grade lameness on one or more limbs, being graded 1 or 2 on an eight-point scale. Nearly half — 47% — were found to have gait abnormalities in canter.
The ethogram scores ranged from 3 to 16 out of 24, with a median 9 — above the score of 8 at which it is considered the animals would feel musculoskeletal pain.
All non‐lame horses with a normal canter had an ethogram score below 8, with a range of range 3–6, with the exception of one riding school horse and one general-purpose horse.
Dyson and Pollard said the ethogram appeared to provide a simple method of determining the likely presence of musculoskeletal pain in horses.
They found that 10 of the 11 riding school horses used in the study had gait abnormalities consistent with musculoskeletal pain.
Also, riders of lesser skill tended to deliver worse scores on the ethogram.
“There are several studies,” they said, “which demonstrate that unskilled novice riders have a less stable position and lack of phase synchrony with the horse compared with riders of superior skill and experience.
“These features have the potential to alter the horse’s head and neck position, lameness, and quality of gaits. However, we have previously observed during clinical investigation of lame horses that, when ridden by a skilled professional, the rider may appear to ride relatively poorly.
“However, when gait abnormalities are abolished by local anaesthesia, the rider then appears to be both more in harmony with the horse and considerably more proficient.”
The authors said the frequency of low‐grade lameness and other gait abnormalities in the study horses was high, reflecting the inability of owners to recognise musculoskeletal pain, as shown in previous research.
“It should be borne in mind that in horses with lameness in more than one limb, as frequently observed in the current study, the grading of lameness may be neither accurate nor reflect the level of discomfort.”
“There was a disturbingly high proportion (47%) of ill‐fitting saddles with the potential to adversely influence performance,” the pair noted.
“However, in the current study, saddle fit did not influence the ethogram score. Nonetheless, a change from an ill‐fitting saddle to a better fitting saddle may have a dramatic influence on ridden horse behaviour.”
Dyson and Pollard said educating riders and trainers about the value of the ethogram for detecting the likely presence of musculoskeletal pain may prompt them to seek professional advice.
Of the riding school horses, 9 out of 11 showed lameness and 6 out of 11 displayed gait abnormalities at the canter.
“The sample size of riding school horses in the current study was small, but if it is representative of the United Kingdom riding school population, the high incidence of lameness and ethogram scores of 8 or more is of cause for concern.
“Behaviours exhibited by many riding school horses are likely to reflect chronic discomfort and should not be regarded as typical behaviour of pain‐free horses.
They noted that, under the Riding Establishments Act (1964), horses must undergo an annual veterinary check to determine that they are “in all aspects physically fit”.
This examination does not require horses to be ridden.
The pair suggest horse welfare at riding schools could be enhanced through the use of the ethogram by veterinarians in their assessment, with the horses under saddle.
In conclusion, they said: “Education of owners, riders, trainers and all associated professionals is required about what constitutes abnormal horse behaviour, so that lame horses are recognised and undergo appropriate investigation and treatment, in order to both enhance equine welfare and improve performance.”
Dyson, S.; Pollard, D. Application of a Ridden Horse Pain Ethogram and Its Relationship with Gait in a Convenience Sample of 60 Riding Horses. Animals 2020, 10, 1044.