Just started feeding Raj garlic powder because I nooticed that the midges were making him scratch and he loved them! So I don't think it will harm trying them. He is 13.1H and I use about 2 teaspoons with him
It works wonders. Both my girls are on it because it is the only thing that works. Fly spray never works for me. The only down side is that when you clean their stalls you can really smell the garlic. It helps alot though. The flys rarely ever bother them now.