Very crumbly hooves.

[Cupcake]

Skye has quite discusting hooves at the moment. I'll try and take some pictures tomorrow night as they are worse than other times.

In the past whenever her paddock gets muddy her feet will be terribly crumbly. They're accompanied by a horrid smell. At first I just assumed it was thrush. So all the other years I've coated them with stockholm tar and a few weeks later they're good as new.

After reading up about hoof thrush, I'm quite convinced it isn't that at all. There is no black substance and they smell isn't as bad as described.

Does anyone have any ideas what it could be?

[Bay Mare]

Is the sole chalky looking? Do chunks fall out? It could be that the false sole is coming away, it can sometimes be accompanied by a nasty smell. You should have some nice concavity underneath if that's what it is. Sometimes the whole sole can come away which is a bit shocking but perfectly normal, the horse is just getting rid of the bits that they don't 'need.

Stockholm tar is toxic btw, I wouldn't use it. It's oil based and will damage the hoof in the long term.

Also consider thrush (you don't necessarily get the black goo) and WLD and treat with something like borax, cider vinegar or honey.