In a new study, ridden horses showing at least one-third of the behaviors listed in a recently developed ethogram (behavior chart) had gait abnormalities and/or subtle lameness.
The ridden horse pain ethogram (RHpE) includes 24 behaviors that have been scientifically validated as associated with pain, said study author Sue Dyson, MA, Vet MB, PhD, DEO, Dipl. ECVSMR, FRCVS. The behaviors include pain-related facial expressions in ridden horses as well as full-body language. Examples include pinning the ears back for at least five seconds or opening the mouth and separating the teeth for at least 10 seconds. Designed specifically for riders and owners, it’s meant to give horse people a relatively simple way to recognize signs of pain in their horses under saddle.
“We have very strongly validated that the behaviors in our ethogram are pain-related,” Dyson said. “And we know that if you take away the pain, those behaviors go away. So it’s a very strong tool.”
Ethogram in 60 “Sound” Riding Horses: 73% Are Actually Lame
Dyson and her team recently applied the RHpE to 60 sport horses and riding school horses in the U.K. They assessed the horses for the presence or absence of the 24 behaviors while being ridden by their regular riders. Before the riding session, the horses also underwent skilled subjective lameness exams and clinical exams checking for back muscle tension or soreness, and a master saddler assessed their saddle fit.
Although all the riders in the study had reported that their horses were sound, the lameness evaluations revealed that 73% of them were lame in one or more limbs, Dyson said. The lameness was subtle—up to a score of 2 on a 1-to-8 scale—and wasn’t necessarily constant, but it was present and reflective of the horse’s discomfort, she explained. Additionally, nearly half the horses showed some sort of gait abnormality, such as bunny-hopping or “moving short” at the canter.
Lameness was strongly linked with a RHpE score of 8 or more (out of 24) in this study, she said. In fact, all but two of the sound horses had RHpE scores lower than 8. These two horses might have had symmetrical limb pain or primary back or sacroiliac joint region pain, she explained. The horses with lameness and/or gait abnormalities generally had scores of at least 8.
Behaviors most associated with lameness in this study included holding the ears back for at least five seconds, having an intense stare for at least five seconds, and stumbling repeatedly or dragging the back feet, Dyson said.
Interestingly, she added, the scientists didn’t detect a clear statistical association between RHpE scores and saddle fit, even though nearly half the saddles in the study showed signs of poor fit. She cautioned, however, that the ill-fitting saddles could still be causing discomfort.
Learning Not to Accept Signs of Pain as Normal
The fact that riders don’t recognize signs of pain or lameness in their horses is problematic, said Dyson. “I am always disappointed when you have a sample of volunteer horse/rider combinations in which the horse is considered clinically sound, and you find that unfortunately it’s not,” she said. “And we see a high proportion of those.”
This doesn’t mean the riders aren’t paying attention to their horses. Rather, it’s probably reflective of the riders’ past experiences with horses and lack of training in recognizing pain-related behavior. Specifically, many people’s first experiences with horses are in riding schools, where the horses tend to have subtle pain due to subclinical lameness, suboptimal saddle fit, and carrying unbalanced and/or unskilled riders, Dyson explained.
“We believe that many riders learn to ride on riding school horses which exhibit these signs, so that there is a generalized acceptance that these behaviors are normal for horses,” she stated. “There is an urgent need for education of riders and trainers at all levels to recognize that demonstration of eight or more behaviors of the RHpE is highly likely to reflect musculoskeletal pain.”