Hmmm, never really had one or heard of one gettting proudflesh from castration. Poor guy. At this point, if he's REALLY got proudflesh in that area, I'd consider being hauled away from the other horses the lesser of two evils. It's an unusual reaction to a common prodcedure, and he'll have to be alone at some point in his life anyways.
Personally, we always cut them in the fall if possible when flies were dying out, and we exercised them mildly, everyday afterwards. It would make them bleed sometimes, but helped to keep it from swelling as bad and drained the area, since it's not a place you easily treat. I noticed each horse is individual, some swell more than others for longer and some scab over more dramatically, but in the end, never did see one have any proudflesh. We didn't even apply anything to the area. (this was at a QH ranch that had several to do at once and were in groups that were weaned together or yearlings-they usually weren't gentle enough to attempt applying salve to that area anyways) we just made sure they had a manure picked out fo the pen. My personal horses I've had gelded, we did a couple in the spring, and they swelled a little more, but there were more flies...
Sorry, I digress...pregnancy brain, I guess. Try the herbal stuff for a few days, or leave it alone and exercise him-walk/trot to get the area to drain...if it's not getting any better, take him in for surgery.
Barefoot and Loving it!
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