white line above hoof

Question
We recently brought our horses to their new pasture (7 days) where it has been dry and has new rich pasture grass. My wife noticed they both now have a white line across the top of their hoofs.( both horses and around all four hoofs) She looked up 'white line disease' but it does not look anything like what the horses have. I was wondering if you had an idea what it might be and why it has started.I am not a horse person so I do not know what other information you would find helpful.

Answer
Hi Steve -

I read your question while I was at work earlier today and have been thinking about it ever since.  I wish you had a picture of this but I think I know what you're seeing.  First, be aware that the horse's hoof grows from the top down.  The line you're seeing at the top of the hoof - I'm wondering if it's a fat, kind of soft and mushy line or a really dry chapped kind of a line.  My thought is that it is the soft mushy stuff which is from the wet conditions caused by the dew and moisture in all that grass that these feet haven't seen in a while or at all.  

What worries me the most is the sudden change in pasture for these horses.  Conditions like this can cause a situation that affects the feet, called laminitis and in severe cases, can lead to founder.  Horse's have extremely sensitive digestive systems and all changes need to be done carefully and very gradually. Since they have been on this pasture for a week now, it is probably too late to begin a gradual change but I would observe these horses carefully.  If you notice them acting sore - short strided, pain while turning around or standing with their front feet stretched out in front of them - contact a veterinarian.

Otherwise, I believe what you are noticing is a normal occurrence for damp conditions. Please let me know if you have further questions Steve ... I'm happy to help!