The conversation of rugging horses will always divide a group, some believe it a must and others are adamant it’s unnecessary. And whilst the argument that horses have survived for millions of years without them has merit, like most topics involving humans interacting with horses, it is important to take all variables into account for each individual.
As with the changes in their diets, the domestication of horses has seen other changes in their living conditions. Rugging can be easily put into this category. If we look at horses of the past and/or observations of brumbys, we see the freedom to roam thousands of acres of changing topography and vegetation. The ability to shelter in caves and thick bush and to grow adequate coats enables them to survive very well.
When we change this situation, we need to be mindful of what we provide and careful at the same time to not over provide! (Come on, we are all guilty of putting one too many rugs on because we are freezing). The fact remains that horses do not require the rugging we believe is necessary to survive – but rather because of our projection of how we feel when it’s cold outside, or because we desire for our horses a certain appearance.
Considering the nature of our disciplines and travelling to competitions, it is wise to take note of temperatures and weather. Amazingly horses can maintain their body temperature in climates that range from 40°C to minus 40°C! Horses require 10 to 21 days to adapt to cold — so if the temperature drops from 20°C to 5°C, the horse will require 2-3 weeks to adjust. If temperature drops to minus 5°C, the horse will need another couple of weeks.
The LCT (lowest critical temperature is the temperature below which the horse must shiver and use body tissue to generate heat) varies between breeds, and is affected by wind and rain, fat, fur and feed. The LCT (when shivering begins) is minus 15 to +10°C for mature horses; minus 3˚C to +7°C for warmbloods; 0˚C for weanlings and foals; +24˚C for sick foals and +2˚C for ponies.
Fat is three times more insulating than other tissues – thin horses need more energy because they lack insulation. A thick hair coat can mask thinness, so it is important to run your hands over your horse regularly to pick up condition loss. Without a thick hair coat, clipped horses begin to shiver when the temperature is 10 to 15°C.
Below the LCT, shelter and/or extra feed, are needed to help horses cope with the cold. Having a shelter where they can also lie down, allows horses to conserve up to 40% more body heat. Energy intake is critical for cold tolerance, because below the LCT, horses need to eat more to maintain body temperature. The LCT for yearlings fed a high quality diet shifts from 0°C down to minus 11°C.
Each horse will have unique needs and it is important to think about all factors in the equation. Age plays a significant role – as with all animals, including ourselves, the young and old require more thought. An aged horse may struggle to maintain a healthy condition over cold periods and likewise a foal or young horse may encounter difficulty. In situations like these it would be wise to provide areas of shelter from rain and wind or possibly a rug.
Shivering increases body heat production by up to 400%. The amount and type of feed affects how much a horse must shiver and in our next blog we’ll explore the best feeding strategies for winter!
Taking the above information, adding the changes to each horses environment and their individual needs enables us to make an informed decision as to what rugs, if any, are required… but always keep in mind, are they really cold or are we just rugging them up to keep ourselves happy and make sure we are good parents??
EQUINE CLINICAL NUTRITION
Dr Jennifer Stewart