Winter laminitis – nowadays also called winter foot pain – is different from regular laminitis. Some symptoms are similar, such as difficulty walking or changing posture to relieve the hooves. Winter laminitis can occur in cold weather (usually during frost). Horses with winter laminitis do not have warm hooves. This is a major difference from regular laminitis, where the hooves feel warm and a throbbing pulse can be felt in the hoof. In winter laminitis, there is no inflammation, so the hooves do not become extra warm.

Not all hoof pain is winter laminitis

Winter laminitis occurs in very cold weather, but a horse that walks carefully in winter does not always have it. Horses recently shod or with thin soles may develop problems on hard, frozen ground. They can develop hoof bruises or sole bruises. Horses with insulin resistance or a history of laminitis may also suffer in winter, especially on sunny winter mornings when grass contains high fructans. In these cases, remove the horse from the pasture immediately if it walks carefully and its hooves are warm.

What is winter laminitis?

Winter laminitis is caused by narrowing of the blood vessels in cold conditions. To keep its core warm, less blood flows to the legs and hooves. In cold weather, the adrenal glands produce more cortisol, a hormone that constricts blood vessels. The thyroid also becomes more active, affecting blood flow to the hooves. In healthy horses, this is not a problem, as enough blood remains in the hooves. Only hoof growth slows slightly. Older horses, or horses with insulin resistance or PPID, are more vulnerable. Horses with previous laminitis damage are also more sensitive to winter hoof pain.

Managing insulin

Since insulin fluctuations also affect blood vessel constriction and dilation, proper management is important for insulin-resistant or PPID horses. This includes low-sugar hay, avoiding pasture with high-fructan grass, no sugar-rich concentrate feed, possible PPID medication, and sufficient free movement.

Preventing winter laminitis: Keep warm, amino acids, and herbs

Sensitive horses should be kept warm with a good blanket, and optionally leg coverings. Hoof boots may help. Keep the horse moving and provide unlimited roughage. Certain supplements and herbs can help reduce blood vessel constriction. Ginger is well known for this. The amino acid L-arginine also contributes, as it supports nitric oxide production, which helps dilate blood vessels.