“Do I blanket my horse, and if so, when?” Variations of this question might be one of the most asked on horse forums around the interwebs. Everyone has an answer, and everyone seems to be an expert, but the problem is that most of the responses come from people who don’t think like a horse. They think like a person who then anthropomorphizes the horse. They make decisions based on a subconsciously asked question of ’what might I want in this situation,’ instead of ‘what might my horse want?’ To know the answer to what your horse wants, one must understand some basic biology of the horse, which we’ll get to later.
But even before we get that far, this super common anecdote might help you understand just how different our own needs and preferences are from our horses: A horse owner has labored - or spent thousands - to build a shelter in her horses’ pasture. Then on that first freezing cold, rainy day after the project is finally complete she looks out to see that, much to her chagrin, the horses have opted to stand outside in a freezing rain storm instead of warm and dry in the expensive shelter.
This speaks volumes as to how big the chasm is between what we find comfortable and what horses find comfortable, but instead we humans often choose over and over to make decisions for our animals based on our own needs and preferences and not theirs.
Here’s another example:
I live in the California desert where summer temperatures regularly exceed 110 degrees, and in my horses’ pasture they have both a sun shelter and trees. On numerous occasions I have seen them standing in direct sunlight when the temps are scorching, even though they have a multitude of shady options where it’s easily 30 degrees cooler. Yet they are standing in that sun for hours on end. And no, that’s not where their food is. Their food is in the shade! Their water is in the shade! A human would actually die in relatively short order if they stood in the sun like that when it’s 115, but horses…not only do they not die, they’re actually quite comfortable and choose to stand there. They sweat, the sweat has a cooling effect as it evaporates, the horse is fine.
But we’re not here to talk about extreme heat, that’s just another example of how different horses are from us. So back to the subject of what to do with blankets in the winter. The list of situations where it’s appropriate to blanket is extremely short, so we’ll start there. They are:
- When your horse is clipped and it’s cold out (think, below 40 which is the critical temperature threshold for horses with summer coats), you’ll pretty much always want the horse to have a blanket on except during work, or if they’re outside during the day, and there’s ample direct sunlight and it’s not windy.
- You’ve just moved to a colder climate within the past 10-21 days. Horses need approximately 10-21 days for their bodies to acclimate to the new regular temps, so for example if you’ve just moved from Florida to Michigan in December, you’ll probably want to be blanketing your horses overnight for the first 10-21 days. After that, with daily exposure to the cold temps during the day, your horse should acclimate just fine to survive the rest of the winter outside sans blanket.
- Your horse is older, is a young foal or lactating mare and/or has trouble keeping weight on due to some other medical condition that your vet recommends blanketing for.
If your horse does not fall in the categories above, it is my very firm opinion that in every single other instance blankets are not only never needed, but they can cause your horse more harm than good. The most important thing you can do for your horse to stay well insulated during the colder months is to make sure they have the appropriate nutrients to keep body mass at the appropriate levels through the winter. Here is a feeding table for reference:
I do not care that it is -50 with a wind chill of -200. I do not care that it is snowing buckets and it’s piling up on your horses’ backs. In fact, especially not if the snow is piling up on your horse’s back! This is proof that his coat is actually working to keep him insulated. If it wasn’t the heat would be escaping the fur canopy and melting the snow on top.
Your instinct as a human being would be to bundle up so tight you can’t move, but you’re a human being. You are not a horse that has adapted over millions of years to be able to withstand a very wide range of temperatures. You don’t see moose in Canada putting blankets on, do you? You don’t see dolphins or whales wearing wetsuits in 40 degree ocean water, do you? You don’t, because these animals are adapted to their natural cold habitats and they not only survive, but they thrive there.
You might say “but we have domesticated horses so surely we need to care for them differently than wild horses.” And I’d say yes, we have bred horses for thousands of years to change everything from their size to their speed, but breeding has made exactly zero changes to the way horses’ skin and hair grows and from their wild ancestors, which has them extremely well adapted to extreme temperatures, even big fluctuations within a 24 hour period.
This applies during cold rainy days too. I know I know your instinct is to think, hey that horse needs a raincoat they’re getting soaked! Because in that situation, you yourself would want to put on a raincoat to keep from getting soaked. But the truth is, your horse is not getting soaked. Their coat is doing a most excellent job of keeping the water off your horse’s skin. As with wild animals, a horse’s skin and hair follicles are designed to respond to temperatures and moisture in a way that human skin is not. When temperatures drop, or barometric pressure changes, or even the wind direction changes, the hair follicles will change their orientation in response. When this happens, your horse has suddenly produced a literal coat of armor against the conditions it’s now facing. Your horse’s body will stay at it’s healthy range.
Here’s the bio lesson I promised earlier on how horse hair works with temperature regulation during all weather conditions:
Your horse’s winter coat is made up of two layers: The longer hairs called guard hairs, and a thick undercoat. The guard hairs help with repelling water away from the body, like little rain gutters. They carry the water down the hair shaft and away from the horse. The undercoat keeps heat trapped close to the skin and prevents it from escaping to the atmosphere. This two layer coat system is a brilliant raincoat/puffy jacket combo, and it works best when left to function the way it was designed without any interference. The increase in body mass for the winter months is like the blubber layer in marine mammals that keeps them warm in the frigid water temperatures.
Now. If let’s say you were to interfere with these processes by, say, throwing a blanket over their fur coats.. you would be creating a very difficult and unnatural scenario for your horse by trapping heat and moisture inside the blanket and inside their coats. Your horse’s internal temperature will rise due to the trapped heat, and to battle this situation he will begin to sweat. His body will have no means of releasing any of this moisture due to the blanket, when liquid is on the skin it draws heat away from the body, and the cold outside temps will give the horse chills, which can lead to colic.
If you’re a skier you may have experienced this feeling yourself when you’ve bundled up to ski in frigid temps, but after having skied a few runs of deep powder you break a sweat inside your jacket. As soon as you stop moving, the wetness inside your gear cools down, causing you to get cold very fast. This is what happens to your horse when you blanket him in cold weather.
I also do not care if it’s the end of the summer, your horse still has a summer coat, and there is a sudden cold snap. Your horse, even with a summer coat, is well equipped to handle these sudden temperature changes too, as low as the critical 40 degree threshhold. Unless it suddenly starts snowing in September, chances are it’s not cold enough to need a blanket. Blanketing in these instances poses the risk of making your horse overheat with nowhere for the heat or sweat to escape to, which is far deadlier of a problem than them getting cold. Horses colic far more often in temperature fluctuations when blankets are involved than when the horse is left to figure it out on their own - and these are facts.
So now that you have a solid understanding in the biomechanics of thermoregulation in horses, I hope you will consider leaving those blankets on the shelf! But consider instead, to provide your horses with an endless supply of forage so they can eat as much as their bodies tell them to eat and that’ll be all the thermoregulation assistance you’ll need to have happy healthy horses all winter long.