Car doors freezing shut, toes stinging when you dismount, water pipes bursting, slipping on ice: if you have ever spent a winter in Canada, you are very familiar with these inconveniences that make day-to-day barn life tricky at best.

Unfortunately, below-freezing temperatures can also create an environment in which your horse is at risk for conditions which can become more prevalent during the winter and be very detrimental to your horse’s quality of life.

Less Water = More Colic

Colic is defined as generalized abdominal pain. It is every horseman’s greatest fear and can become life-threatening if not diagnosed promptly and treated properly. Abdominal pain most often originates from the gastrointestinal organs – the stomach, small intestine, cecum, and large intestine – structures that can become obstructed (impaction colic) or can have their blood supply cut off (torsion or displacement colic). Dehydration can cause spasmodic colic, and a sudden grain overload can cause gas colic – any of these situations can require surgery.

Clinical signs of colic include, but are not limited to: frantic pawing, rolling, flank watching, decreased manure output, and flipping the upper lip (flehmen response).

Why do certain types of colic become more prevalent during the winter months? Horses tend to drink less water when it’s colder, similar to humans. This is because they sweat less when it’s cold outside (especially if they are clipped!). Less sweat means less water loss, and a lower drive to replace it by drinking. If pipes freeze, or buckets freeze over, horses also don’t have access to as much water as they need, so it is very important to ensure there is no ice in buckets or water bowls. Less water in the GI tract to facilitate movement of food particles from the mouth to the rectum can cause food impactions, most often in the large intestine.

Any type of colic requires veterinary attention. Before the vet arrives, if you believe your horse is colicking, remove all food from his or her stall, but leave the water. Your vet will complete a physical exam and most often, a rectal exam, which gives him or her more of an idea as to what is going on inside the horse’s abdomen. Another treatment your vet will perform is inserting a nasogastric tube (NG tube) into your horse’s nose. This lengthy tube is passed from your horse’s nostril, down the esophagus, and into the stomach. An NG tube is used to ensure a horse’s stomach isn’t too full and also to deliver water or other medications to treat the colic.

Because horses cannot vomit, it is essential to ensure that during an episode of colic their pain is not coming from an extra-full stomach. The stomach can become over-dilated due to an obstruction further along the GI tract, which prevents passage of fluid from the stomach. If the pressure is not relieved via NG tube, the stomach can rupture, which can be fatal.

Good management is key to preventing most colics. Ensuring proper water intake (unfortunately, this may mean toting water to the barn from the house), feeding easily-digestible food (and making sure the feed room is secured against raids), and providing regular dental care and deworming for your horse are recommended. Wetting feed or adding extra salt to your horse’s breakfast are great ways of encouraging more water intake.

Breathing Issues

Heaves, or Recurrent Airway Obstruction (RAO), is a common winter ailment which affects some horses beginning around nine years of age, and will continue to affect them for their entire life. It is a performance-limiting, allergy-induced respiratory disease characterized by nasal discharge, chronic cough, and difficulty breathing. These clinical signs usually make an appearance when a horse is stabled, bedded on straw, and/or eating hay. They are caused by inflammation of the small airways within the horse’s lungs. Along with mucous production and bronchoconstriction, a narrowed space for air to pass through the lungs is created. This results in difficulty breathing, usually with an increased abdominal effort that results in a “heave line” – an area of muscle hypertrophy.

Straw contains a lot of dust, which can be an allergen. Round bales of hay, or even large square bales, can also contain multiple allergens. Feeding from large bales enables horses to stick their entire head into the bale and when they inhale, they are exposed to increased amounts of these allergens as the particles are disturbed.

Horses often spend more time inside during the winter, and therefore this season can be especially taxing on those affected by RAO due to the reduced ventilation in the barn. Barns with especially poor ventilation often have more than one horse suffering from RAO.

Treatment of heaves can be difficult, because a large portion relies on careful stable management. Medications prescribed by your vet include bronchodilators to immediately relieve the symptoms, and corticosteroids to further control them. These bronchodilators can be oral or inhaled through a puffer and while they can help with symptoms, if the cause is not removed, the medications simply act as a bandaid. In an ideal world, the affected horse would live outside with grass as its main source of roughage. Even good-quality hay hosts allergens, which can elicit a recurrence of RAO symptoms. Unfortunately, grazing is severely limited in the winter in most of Canada, so grass can be supplemented with pelleted feed to ensure sufficient calories are being ingested.

Skin Disorders

Contagious fungal spores (ringworm), bacterial infections (rain scald, mud fever) or parasitic insects (lice, mites), can also cause misery for your horse in the winter.

Ringworm typically causes circular areas where the hair falls out. The animal should be isolated, treated with an over-the-counter antifungal dressing and all saddle pads, grooming tools, etc. used on that horse must be disinfected.

Lice (pediculosis) thrive in cold weather in long hair coats, causing intense itching when they feed. There are specific sprays and powders used to eliminate them. Mites cause itching and scaly skin, skin inflammation, hair loss, pustules, bloody crusts or even mange. Treatment may include hot lime sulfur spray or dip, topical pyrethrin and/or oral ivermectin or oral moxidectin. Both mites and lice can be transferred from horse to horse via direct contact or tack/brushes.

Rain scald and mud fever attack chronically wet areas of skin, such as on the lower legs, or sweaty areas under blankets, causing crusty scabs which bring the hairs with them when scraped off. Your vet can prescribe topical steroid and antibiotic ointments, or you can wash the horse with antimicrobial and antibacterial shampoos and keep the area dry.

Stiffness and Joint Pain

Cold and damp weather and lack of exercise can exacerbate joint pain and stiffness caused by osteoarthritis or old injuries, especially in senior horses. Gentle exercise and regular turnout can help keep things moving. You may consider adding a vet-recommended joint supplement to your horse’s diet, applying soothing liniments, or using massage therapy or non-steroidal anti-inflammatory drugs (NDAIDs) or other pain-relieving products to make the winter months more bearable.

Weight Loss

Staying warm burns calories, so horses need to increase their caloric intake during the winter or weight loss can result. Adding 1-4 flakes of extra hay, rather than extra grain, is recommended, especially if the horse’s workload is decreased. The fermentation in the hind gut which takes place during the digestion of hay produces heat to keep the horse warm while providing additional calories. Geriatric horses are especially at risk of weight loss, as their digestive systems may be compromised due to lower populations of organisms in the microbiome, ulcers, or due to chewing problems because of poor teeth. A specialized senior feed and/or the addition of oil to the diet can help. And don’t forget to have your vet or equine dental expert examine your horse’s teeth for uneven wear or other problems a couple of times a year.

While caring for your horse during the winter months may be more of a challenge, being prepared and alert to changes in behaviour and outward physical signs will allow you to be proactive in their care. As always, speak with your vet if you have any concerns about how to keep your horses safe, happy, and healthy in any season.