This is interesting, because we clip
them onto the cows' ears and the tags hang like earrings. I suppose since
cows flap their ears, the insecticide does get onto the skin. It was
always my assumption that the fumes from the tags were what killed the
flies. I learn something new every day.
The studies that say that they don't work are based on hanging
them on halters. Because they are slow release, they depend on getting
in contact with the skin and absorbing into the oils in the coat.
