My horse, Logo, began rubbing his crest aggressively a few weeks ago.  My first thought was threadworms because I had seen some discussion of that here.  I had never heard them mentioned before.  My daughter (a vet) thought it looked like sunburn.  The crest of his mane has always been sparse, due to overaggressive mane pulling we surmised.  I put silvadene on twice daily and washed it off daily.  It’s looking much better now but I still keep a fly sheet with neck piece on him to shield it from the sun.
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