The flies here in western Michigan are terrible this summer. I've tried rubs - which my beef cows avoid at all cost - and sprays - they run as soon as I pump the sprayer one time. A friend of mine told me that she heard that feeding cattle garlic or putting cider vinegar in their watering tank would help rid the flies. Has anyone tried either of these before? If you have how much garlic or vinegar is needed? Thanks for you help!