My horse is having these right now. I have been soaking and washing off the scabs with a weak solution of Dawn dishwashing liquid. When there is a hairless, pink patch showing, I rinse and dry it off and spray it with athlete's foot treatment that I use on myself. I have been using Lotrimin spray powder. I check the spots daily and retreat when necessary. The first ones are going away and hair is growing back. I am happy with the results of this treatment process for my horse.
Well that's exactly how mine started on my chestnut, white legged horse (I am also in Northern California and it started in hot, dry weather). The good news is you are catching it early on. I followed all the scrubbing/washing/goop recommendations on here and mine spiraled out of control. It starts with something irritating the skin, then the body reacts to that. The scrubbing only irritate the skin more and opens it up to infection.
I would keep them dry and out of the sun as much as possible and start with having your vet prescribe some sort of anti-inflammatory. I used Genesis spray with an oral antibiotic/steroid but some vets also try panalog (which is an anti-inflammatory, antibiotic and anti-fungal). I would also switch to wraps on the legs rather than boots that would irritate them. I will say that if they don't start getting better really quickly with use of a topical anti-inflammatory I would go see a dermatologist.
How far are you from UC Davis? They have an awesome dermatology department, I love Dr White.
This is excellent advice. I've dealt with the same issue on my TB gelding's white legs for years and it just gets worse each time. It used to go away completely at times but now it's year round with it getting worse in warmer months. Moisture seems to play little to no role. I wouldn't attempt anything topically other than protective cream (desitin) and sloughing off scabs via gobs of antibiotic ointment under wraps which softens them and they come off on their own after a few days of the un-wrapping/re-wrapping process. Anything more aggressive made it worse. A dermatologist is your best bet if you can't get it under control.
Has anyone tried immune support to help tackle this? I'm thinking oral vitamin supplementation.
I cant open your pics, windows 8 stinks!!
I wonder if it looks like what Draft horses easily can get under their feathers. Round scabby pink sores, size of a quarter?? When left unattended for long, it will ooze and get wormy things inside of it (??) . They will eat through the flesh
/bone and make your horse lame and miserable for months. In Florida I had Friesians with this issue, it was a royal pain because of the humidity. It has a complicated name (google) and you need to treat it from the inside (drugs) and the outside: daily cleaning, anti bacterial creams, keep dry but let air in which is difficult etc....fingers crossed that it is not the same thing, or at least not this bad!