Laminitis And The First Frost

Laminitis is a disease of the foot which causes inflammation of the laminae. The laminae act like Velcro, holding the pedal bone to the hoof wall. When they become inflamed, this attachment is compromised, leading to symptoms which vary from mild lameness to life threatening rotation and sinking of the pedal bone. Whilst many of us are well acquainted and informed about laminitis occurring during the spring and summer, unfortunately we also have to be aware of this disease being triggered by cold weather.

Certain environmental conditions, including low temperatures, cause sugar levels to increase in the grass. An idyllic winter’s day can therefore be dangerous to horses and ponies prone to laminitis. Bright skies with plenty of sunshine allow the plants to photosynthesise during the day, and the subsequent cold night leads to storage of the sugars that have been produced. When horses eat this sugary grass, the amount of glucose in their bloodstream increases. This in turn causes a rise in insulin levels which has been shown to cause laminitis. It is important, therefore to keep your horses off the grass in these conditions.

There are other potential issues in the cold weather too:

• Horses with insulin resistance, and those that have suffered from laminitis earlier in the year (especially if there has been rotation or sinking of the pedal bone) are more likely to be painful on the frozen ground. This may be due to abnormal conformation of the foot, but might also be explained by poor blood flow within the hoof capsule
• Whilst horses suffering from active laminitis must be on strict box rest, exercise is key to the prevention of laminitis. Many horses are exercised less in the winter, therefore less glucose is used up by the muscles, and there is more in the circulating blood
• Soaking hay is less effective in colder water and therefore the amount of sugar in the diet may be increased

What can be done to help prevent laminitis in the winter?

• Prevent or reduce turnout (a grazing muzzle can be useful to reduce grass intake) until night time temperatures increase above 5°C and the weather becomes overcast
• Soak hay in warm water, and consider having your hay analysed to ensure that the water soluble carbohydrate level (sugar and starch level) is less than 10%
• Ensure feet are appropriately trimmed. X-rays may be useful to help guide this
• Protect the feet if necessary, boots and wraps may be appropriate in some cases
• Reduce your horse’s calorie intake if they are not being exercised as frequently

If you have any concerns regarding your horse and laminitis this autumn, call the clinic on 01323 815120.