We've worked on this problem for years, but i thought I'd throw out the question for the group as I'm fairly new on this site. We have an Akita that spends most of her day out side. Our yard is around 3 acres fenced so she has plenty of room to roam. Every summer the poor thing ends up with flies biting the tips of her ears until they bleed. We've tried fly ointment and sprays, but it rarely last the full day and I'm worried about applying it daily. We have fly catcher bags up, they work but don't keep the flies off her ears. I should mention we have 8 dogs and most of our neighbors have at least two. We clean up poo every other day or so (too much to keep up with daily) and I'm sure that's the source of the flies. Do citronella collars work? Is there anything you can feed a dog that keeps the flies from hatching in the poo? Any suggestions?