In regards to "Sensitivity to insect bites", Pat in FL sent the following reply on 06/02/2010 (Thank you !!)

There is a bug called a 'no sim' that bites and it HURTS!  We also have something called horn flies which were named b/c they tend to bug deer when they are shedding their velvet, but love horses too and they hurt as well.  I've noticed the no sims tend to leave the small whelps behind as do the big horse flies.  Ever since Hurricane Ivan, it seems like people and animal allergies have increased in intensity and increased in the sheer number of things to be allergic to.
 
What can I say. Florida and the south-east do it big and do it right :-)  For future reference, draft horses can have 10-12 generic chlortrimaton tablets 2x a day to relieve allergies (8-10 tablets 2x a day for smaller horses).  We have a pharmacy here in town that caters to horse owners and a bottle of 1000 tablets is only $17.50 so its worth it.