Genia,

I give my dogs this product called "prozyme" which is a plant based enzyme that is proven to not only help with absorbing nutrients from food, but it's supposed to help with much more, including flatulance(sp?)...I have not smelled a dog fart since they have been on the stuff. Might be worth thinking about. It's just this powder stuff that you sprinkle over their food and it works great. If you do a search for "prozyme dog" on your browser you can read more about it and compare prices. I buy the large container (I think 454) and it's around $30 with shipping...and lasts 4-5 months.