One of the simplest treatments for foot problems, and already mentioned by Sally, is simple lime. The beauty of it is that it requires no skill or special equipment and it is particularly effective in this wet weather as it not only kills the bacteria, but dries the feet up as well.
Just put some powdered lime thickly on the ground wherever the sheep regularly go, eg gateways, troughs, under mineral buckets etc. You need to keep adding more as it gets puddled up, but you will be surprised how soon the sheep's feet improve and for minimal effort.