Extremely common, yet often undiagnosed condition, a stretched white line is in fact a symptom of subclinical laminitis. This results in a dysfunctional internal support mechanism and the white line becomes wider than what is normal. As this happens, the hoof is stretched out of shape.
What does this mean for my horse?
There are one of two things happening in this situation - either your horse has mechanical laminitis (the hooves are not functioning correctly) or it is in a state of subclinical laminitis (due to sugars - see our article on laminitis).
Depending on the state of the hooves, horses can show no sign of lameness at all, or can be in extreme pain. Which becomes more apparent when you take them onto hard ground. Tenderfootedness, especially on the rocks is a key indicator your horse is experiencing some form of internal metabolic distress or poor hoof function.
Why does this hurt? When a horse puts weight on an affected hoof, the wall itself is pulled away from the delicate internal structures of the hoof. A hoof may appear robust on the outside, but don't be fooled thinking its like this all the way through! When a stretched wall bears weight it results in bleeding and damaged tissue on the inside. Want a more personal idea about how this feels? Push a pin underneath your fingernail and you get the picture.
If you horse has subclinical laminitis, their digestive system has been compromised by an imbalance in their hind gut. Alternatively, if it is the result of mechanical failure you will need to think about how often you have your horse trimmed (every 3-5 weeks is the usual ideal). As a pathology, it should be taken very seriously as it is clear warning your horse needs help. If left unaddressed your horse may eventually founder, which can result in death.
How can I recognise it?
Clean the underside of the hoof and give it a brush down. Where the sole meets the hoof wall look what is happening. It should be a solid connection. If however there is an area that has a feathered or textured appearance which stretches out towards the outer wall you are looking at a stretched white line, and in fact laminitis.
Symptoms often include discomfort of the foot, shifting weight, and being tender on surfaces harder than grass. A stretched white line is often accompanied by cracks, but this is not always the case. Usually, the hoof will also have lamellar stress rings which are another indicator of laminitis. Hooves can also take an unnaturally long appearance in the toe, which gives them the appearance to be running away from the leg.
How can I help to see this healed?
Often a symptom of subclinical laminitis it is no less dangerous than the more acute forms, and rehabilitation should be taken seriously.
If it is dietary related it is caused by metabolic distress and gut flora imbalance. Your priority should be to identify and remove the causes that have allowed this to happen in the first place. Dietary and chemical influences that may be responsible for this pathology should to addressed immediately.
Alternatively, if it is the result of mechanical hoof failure you should contact a reputable hoofcare practioner and arrange a trim and assessment, along with a regular trim schedule as soon as possible.
It is important that the trim is balanced in the way your horse needs the balance, failing to do so can result in added pain or discomfort (exactly the opposite of what you are aiming to achieve).
How can I make sure this doesn't happen again?
It is possible to grow and maintain a hoof with a tight white line. The key to this success requires that your horses diet is normalised to match their true dietary requirements. This has nothing to do with the feed and marketing industry. Keep the feed as simple as possible and follow NHC guidelines to grow a solid and healthy hoof. You can see our dietary recommendations here.
Putting your horse through a detox program which is periodically repeated can help to keep their entire system operational.
Follow a regular hoof maintenance schedule that works alongside your horse, rather than against them through unnatural trimming practices.