14/05/2021
We see it everyday in winter and cooler nights leading up to
Over Rugging, by our vet Lucy Carmichael
As temperatures drop, it’s tempting to reach for one of the rugs in our horse’s wardrobe. However, when we want to throw on the layers, doing the same for them may not be the right choice. There are significant differences in the way horses stay warm to the way that we do, for example:
• Unclipped horses already have a thick, hairy coat. This coat contains natural oils to repel water, and, if required, small muscles can contract, causing the hairs to stand on end (much like when we get goosebumps). This traps air between the hair and skin, providing an additional layer of insulation
• Horses have the benefit of a wider thermoneutral zone- for humans this is 25-35˚C, whereas the horse’s thermoneutral zone extends much lower, 5-25˚C. The thermoneutral zone is the temperature range at which an animal does not have to expend any energy to keep warm. This means that horses remain comfortable at significantly lower temperatures compared to us
• Where we have an appendix, horses have a caecum. The caecum acts as a ‘fermentation vat’, where bacteria break down feed and produce heat. Breakdown of forage generates the most heat. Therefore, a diet of low-calorie forage is far more effective for keeping your horse warm than putting on a rug
• Horses can efficiently divert their blood flow from the extremities to the internal organs, maintaining their core temperature. This is why their ears sometimes feel cold to touch, and it is important to see how warm they are by feeling inside the armpit or taking a re**al temperature (See our video on how to take your horse’s TPR here - https://youtu.be/_bug-U1-hMg)
• During movement, or even shivering, contraction of the large muscles of the body burns energy and releases heat
Over-rugging will affect your horse’s ability to regulate its body temperature and may cause significant distress if they get too hot. Extreme heat stress may result in dehydration, increased heart and respiratory rates, lethargy and even colic. There are long term implications too. When rugged, your horse will use less energy, and the excess will be converted to fat, predisposing them Equine Metabolic Syndrome and laminitis in the spring. Therefore, rather than rugging, providing appropriate shelter and ample forage are likely to be more effective ways of keeping your horse warm through the winter.
There are cases, of course, when rugging is appropriate- horses standing in, or those which are clipped will need a rug. However, numerous factors should be considered when choosing which type and weight, including the environment, type of shelter available and the weather. Remember that you are likely to be making this decision in the morning, when the temperature is probably several degrees cooler than it will be in the middle of the day.
For further advice on rugging in the winter, call our team on 01323 815120
