Are we over rugging our horses and ponies?

snowfall is less of a worry than rainfall.
Stabled horses are exposed to greater changes in temperature than those that remain outdoors. So if your horse remains outside it should acclimatise to winter temperatures. However they may become more sweaty if exercised taking longer to cool down. 
Some horses are able to tolerate temperatures as low as 16 and can therefore manage without a rug. However if a horse is groomed or bathed a lot the natural oils can be removed from the coat. This makes them less waterresistant. Horses that are fed adlib are able to adjust their food intake according to the temperature therefore are more likely to manage in colder temperatures.
What are the consequences of over rugging?
Horses create heat through the food that they eat. If this isnt used to keep them warm it can be stored as excess fat providing an extra layer of insulation to the body.
Most are expected to lose weight over winter as their resources are used to keep them warm. However due to overrugging overfeeding and underexercising many horses and ponies are overweight as they come out of winter. Carrying excess weight can cause serious health problems especially as new grass starts to appear in spring. Overweight horses are prone to Equine Metabolic Syndrome and can suffer from Laminitis a painful and sometimes fatal condition. 
How else can I keep my horse warm?
A horse reacts to cold temperatures by seeking shelter and huddling close to others. Therefore providing a field shelter can be much more effective for the horse than wearing a rug. A shelter enables the horse to selfregulate their temperature by choosing to be inside or outside.
It also provides a cover from rain which can often be more important than protection from a slight drop in temperature. A shelter is especially useful on days when the temperature and weather conditions are changeable as a rug on a warm day can result in the horse becoming too hot.
Summary
Horses that are poor doers clipped very young or very old or horses living in extreme weather conditions will probably benefit from being rugged. However many horses will only need a light rug such as a rain sheet to protect them from the elements.
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