So glad this old thread popped up. Done lots of reading and research since I posted this and learned quite a bit. Yes, people do use it, but there is a study that shows ivermectin as an ineffective wormer in poultry (see below) as well as several posts from people that lost birds to worm...
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In poultry, people use the 1% injectable orally, topically and they also inject it. There is also a 5% pour-on that people use topically in poultry.
-Kathy