As autumn moves into winter, the rugs are out and most horses are wearing them. But there has been a lot of publicity recently across social media and other channels about whether horses are being rugged too early in the season and just over rugged in general.

Horses generally cope better with cold temperatures than humans, they are, after all, designed to live outside. But it is not unusual to see hardy types like cobs and native ponies rugged on an autumn day and isn’t the old adage that a native pony in good health does not need a rug? Certainly, native ponies grow a very thick, double layered coat which has air pockets between the two layers. This keeps their skin warm and dry and in fact, putting a rug over this actually flattens out the air pockets and prevents the coat from working as nature intended, far more effective than any rug. Vets have been warning of the health issues that surround over rugging horses for a while now but is there any actual data on the effects of this?

At the International Society of Equitation Science (ISES) in Rome this September, an MSc student presented the findings of a pilot study designed to study just that. The concluding report states that horses can comfortably maintain their body temperature between 5C and 25C in a mild climate, this is for adult horses. This range is referred to as the Thermoneutral Zone or TMZ. Compare this to humans who have a much smaller TMZ of 25C and 30C. So, when we may feel cold, the horse is actually still quite comfortable. Unfortunately, many rugging decisions are based on what the owner is feeling and by looking out of the window.

The study looked at a selection of horses both stabled and at grass and different types of rug including light quilted stable rugs, fleeces and sweet itch rugs. The study also included horses who did not routinely wear any rug. The environmental temperature was calculated by using loggers on the stable door or in the field as appropriate. The horses’ surface temperature was recorded using sensors just below the point of hip. The loggers recorded continuously for twenty-four hours.

Data recorded some obvious findings. Warmer rugs kept the horse’s surface body temperature at a higher level than a thinner rug. But of more relevance is that the rugged horses were significantly hotter than the control horses who were without rugs, in some cases the surface temperatures of the rugged horses were nearly double those of the horses who were not wearing rugs. The research concluded that some rugs can increase the horse’s temperature to a level where the horse is not comfortable and may, therefore, impede the horse’s own ability to regulate his core temperature. The researcher concluded that selecting the right type and weight of rug for the environmental conditions and each individual horse was absolutely vital. And thereby hangs the tale because that still gives plenty of scope for good old human error and fallibility to come into play. If you ask three people on a yard which rug to put on a particular horse, they will probably all give a different answer.

We all love our horses and making sure they are warm and well cared for is part of the bond with our equine friends. Some owners just find it really hard to be objective particularly if they are in the habit of rugging or over rugging. This is a hard habit to break because in their eyes, leaving the horse without a rug or putting on a lighter rug is somehow adversely affecting their horse’s welfare and reflects on their stable management.

Horses are certainly getting fatter as are people and there could be a link between the overuse of rugs and a horse’s weight. The research concluded that more work is needed to understand the impact that rugs have on horses’ thermoregulation and also the condition of their skin. Perhaps if there was empirical evidence that overusing rugs could really damage the horse’s wellbeing then owners would begin to think twice about which rug to use and, whether their horse actually needs a rug at all.