To head off the likelihood of that happening, I got to drive an extra 20 minutes past the barn to go pick up some antibiotics and bute from the vet. We fed her a load of grain with molasses and applesauce to get the meds down her. She was dubious at first, but cleaned her bucket. Hopefully she doesn't wise up on us over the next week or so.
The wound doesn't look too bad, but the potential for swelling is the main concern. She's quite lame on the leg at the trot. Normally I wouldn't worry much about a wound this size, but the barn owner never calls unless she thinks some kind of action should be taken. Since I don't make it out to the barn every day, I'm glad the owner is so attentive and keeps her boarders informed.