Horseflies are the bane of my existence. I hope somebody has some suggestions. I have tried every kind of spray I can think of. A fly mask with ears (I put spray on the ear part of the mask) helps the head and ears. They bite us when we ride. They make my poor (already somewhat psycho) Princess go crazy. Those things hurt!!
Where is he bleeding? Some horses are most sensitive to flies than other. You may want to look into a fly sheet if it's severe enough.
Either way, I would also invest in fly boots. My boy just wears a mask and fly boots and he is perfectly content. Because the lower legs of a horse are so sensitive and have poor circulation, that needs the most coverage. It will also save him from stomping the flies and cracking his hooves.
On the fly spray note, what are you using? Perytherins (i'm sure I spelled that wrong) is the active ingredient in fly spray. The higher the %, the better the fly spray. My personal favorite is are the Parana brand sprays (bright yellow bottle). They are also cheep. Rubbing fly spray into his coat with a towel should help it last longer. Try not to apply fly spray more than twice a day, it may irritate his skin.
My gelding has the same problem, but he doesn't bleed.
1) Try a fly sheet, fly mask and fly boots
2) Use "wipe n' spray" fly spray, but if your horse has sensitive skin it would not be a good choice, I would then use Branco
3) Use a feed supplement, there are many you can find on smartpak.com for cheap
4)You could try Equi-spot as well, but I have not personally used it
I understand how frustrating it can be! I hope this helps, good luck :)
Were having the same issues! I ride him at night because it's too hot to ride during the day here. It's been 90-105 degrees lately. It takes about 5-10 minutes before we have a good 3-5 of these Bastar:(s all over my horse. Luckily none have actually bit him yet because I have a pretty good aim! I can tell one is on him because his whole body starts twitching and his ears go straight back, he even shakes his head. The last ride two nights ago I went on a trail with him and five minutes later we had a swarm that I couldn't keep off of him by my perfect aim, so we ended up galloping for the barn! Mind you there were ladies stqnding outside the barn watching us haul butt back! They thought he took off on me. Haha.
His fly spray works on everything EXCEPT for these huge horrible flies!
We also need a solution. Im really contemplating just bringing a fly swatter with us but that might turn out bad seeing as my horse might see it as a crop (he's an ex race horse) lol.
I don't know what your barn/turnout situation is like, but when the weather is super hot here, and the flies are really bad, the horses stay in the barn during the day and spend all night on turnout (instead of being on turnout all day and in the barn only at night). It really seems to help.
Some biting flies are attracted to the animal's movement, others to carbon dioxide and body heat. I built a Manitoba Fly Trap (google it) and it helps with those in the yard. It does nothing for those on the trail. The warmer the horse gets the worse the flies converge. I rode with a fly swatter. One horse figured out that my wielding a fly swatter seemed to work and would stand while I smacked them. I suspect the smack from the swatter doesn't begin to compare to the bite of a horse fly. I would often get as many as 20 in one session and he'd enjoy a break from them for a while.