The way I always tell thrush is by the smell, so it's hard to tell from your photo.
But here are my favorite thrush cures:
If you're seeing kind of a black, greasy gunk in the hoof, then it's probably caused by bacteria. Go to Tractor Supply and get a box of Tomorrow cow mastitis treatment. There are about thirty syringes inside filled with antibiotic. The syringes have this great extension on them that allows you to squirt the stuff down into the little crevices and holes in the hoof. Save those syringes, too - they're real useful for lots of different jobs.
If you're seeing whitish spongy stuff it's probably fungus, so the antibiotic won't do you any good.
If you're not sure which you have - fungus or bacteria - you can mix up a tube of antibiotic ointment with a tube of athlete's foot or jock itch cream. If you have some of those Tomorrow syringes you can pack the cream in there and use it to apply to the hoof. Get it into all the grooves and nooks and crannies. If not, you can mush it in there with your fingers.
I can't use any of those commercial thrush preparations like Thrushbuster or Hoofflex because even the ones that say they don't burn hurt Conjure's sensitive little tootsies after one or two applications. And he's very prone to thrush once the grass starts coming in and stays that way till it dies in fall. I use the cream every few days just as a maintenance/preventative. If he's already come down with it, I apply it every day for a week or ten days.
Thrush absolutely makes my horse footsore.