The title says it all... so, I saw in a SmartPak magazine an ad for a supplement called SmartBug-Off. If any of you know SmartPak, you know how in some of the magazines they have a profile of a horse who has been fed that supplement, and then how well it worked? Well, in this one, the owner says that they don't even need to use fly spray on their horse anymore (they live in Texas). About a year ago I considered using a different feed-through fly control (not from SmartPak) but that one only prevented flies from laying eggs in the manure, this one seems different.
Any reviews/opinions would be great. Oh, and my mares both get additional supplements, one of which being a feed through dewormer, if that helps.