My horse is chestnut with very sensitive skin. This spring his skin erupted with crud and he lost large patches of hair. He had weeping, crusty, scabs on his neck, underbelly & rump. We treated with Chlorhexadine bathes per the vet, which has helped tremendously, but we're still battling it. We also spray him with an antibacterial solution. I found more scurf crusted all over his tail last week and started using MTG along with the other things. My thinking now..could this be diet related? Is there something missing from his diet that would give his immune system the ability to fight this stuff off, or will we continue to bath and spray him and hope eventually it goes away... Thoughts..
To add to Chocomare's post, take a good look at what you're feeding (by weight, not by volume) and see how much of your horse's nutritional needs are being met by his current diet.
Sometimes the diet can be OK, but you can have underlying issues going on—an undiagnosed/untreated infection/other illness—that's stressing the immune system, allowing various skin funk a better chance of becoming a problem.
Copper, zinc and flax are all good for coat/skin, but you'll want to have a look at your horse's current diet before adding more trace minerals (be sure you're addressing a deficiency, not inviting toxicity). Selenium and vitamin E (they work together) are also somewhat implicated in skin/coat well-being, but more in muscle growth/development.
Are you using fly spray? I have seen a few horses over the years, all chestnut that actually got blistered by fly spray and were very scurfy.
Agreed, it may be a sensitivity or an allergy. If I use the wrong fly spray on my sorrel mare, she breaks out in hives.. then the hives get all crusty.. then they flake off (with the hair attached) and ooze.
"A Joyous Occasion", AKA Joy - 1997 AHQHR Mare
"Hollywood Blue Gold", AKA Fame - 2011 PHA Filly