Late winter/early spring is a time of great changes. The weather warms, then cools. March snow is mixed with days of rain and its resulting mud – and with the mud and inclement weather, our horses are more susceptible to a number of springtime woes. Paddocks and turnout areas are damp and wet in places and, mixed with manure and other wastes that can accumulate, may lead to the growth of bacteria that can ultimately lead to thrush.
Thrush is a common foot ailment in horses, caused by a bacterial infection that often arises under poor hygiene and poor stable management practices. The condition is often the result of standing in dirty stalls or stables or in wet, muddy conditions for prolonged periods of time.
Thrush often occurs during late winter/early spring, when the cold, wet weather may cause horse keepers to be reluctant to spend as much time outdoors as is necessary to keep their horses properly groomed, their hooves cleaned out regularly and their turnout areas cleared of organic matter and waste.
Sometimes referred to as hoof rot, thrush occurs when the horse’s frog, namely the central and collateral sulci, are infected with bacteria. The bacterium that causes thrush exists in our soils and grows in anaerobic conditions, such as up in the deep crevices of the horse’s frog, where there is no oxygen. The affected hoof will have a characteristically foul odor emitted by the infected area.
When using your hoof pick, you’ll find that the frog is moist and deeper than normal, with a thick, black discharge. It may be found in any or all four feet, but most commonly in the hind feet.
Thrush is not contagious, but it can lead to serious problems in the affected horse if not treated. It can be painful for the horse as the frog becomes inflamed; the infection may penetrate the sensitive structure of the horse’s hoof and form an abscess, and can lead to degeneration of the horn and lameness.
If your suspect that your horse has contracted thrush, you’ll need to be diligent in the care of their feet. Begin by providing a dry, clean stall or place to stay. Use a brush and hoof pick to thoroughly clean the frog, sulci and any cracks. The affected area should be removed and trimmed either by a veterinarian or your farrier.
Flush out the area with running water and an astringent or recommended disinfectant. Once you have cleaned the hoof and removed the infected area, spray with a thrush treatment, such as Kopertox or Thrushbuster, which are commonly found in tack shops and feed stores, or other medication recommended by your vet.
Check your horse’s progress daily, cleaning the hooves at least once a day if the hoof was not bandaged, depending on the severity of the condition. If your horse has a mild case, leave the hoof uncovered and exposed to the air, which will help the frog heal (providing the horse’s environment is kept clean and they are not subjected to standing in mud). Daily hoof cleaning, along with use of an astringent lotion, thrush treatment or an antimicrobial solution will aid in recovery.
The use of a bar shoe may help in the regeneration of the frog after the disease process has been halted. The prognosis is usually favorable, provided the condition is found early enough before the corium (the part of the hoof that produces new growth) has been damaged. Under clean and dry conditions, and with daily treatment as suggested above, the hoof should heal within about seven days.
Preventing thrush is important for horse keepers. Start by maintaining clean, dry and sanitary standing conditions for your horse. Use of gutters and downspouts on your barn or run-in sheds will help manage rain and snowmelt in paddocks and turnout areas, as will proper drainage. In larger turnout areas or pastures with wet or muddy areas, make sure these areas are drained as soon as possible. The use of temporary fencing to keep the horse away from the mud will be helpful.
Be sure to remove manure and other organic waste under run-in sheds and keep stalls cleaned on a daily basis. Exercise is one of the best ways to prevent your horse from coming down with thrush, as the movement of the feet will encourage better circulation in the frog. Clean your horse’s feet daily, making sure to pick out all the mud or manure as deeply as possible on both sides of the frog as well as in the cleft area.
Have your farrier come on a regular basis to trim the frog just enough to keep dirt and debris from being caught in the foot, and remove any flaps or pockets that will trap stones or dirt. As another preventative, after cleaning the feet, you can apply a mixture of apple cider vinegar and water using a squeeze bottle such as an empty dish soap container.
The length of time it takes to cure thrush depends on how severe the case is and how diligent you are in treating it. Proper management and sanitation are of utmost importance; under clean and dry conditions and with a once- or twice-daily cleaning and application of the astringent product, the hoof should heal after several days, possibly within about a week. However, if the problem persists, contact your veterinarian.
by Judy Van Put