Have you tried Rocky Mountain Taste of the Wild catfood? One of my devons doesn't cover his bm and when they were on Innova EVO also had the issue with the odor.

Both devons have been on Rocky Mountain for the last 5 months and I am so pleased with the results. It is a grain free formula & has roasted vennison and salmon, sweet potato and other veggies.

http://www.tasteofthewildpetfood.com...eline_formula/

First I went to my local pet store and picked up a small size bag to see how they would take to it. Once I was sure BOTH cats were eating it (they actually were looking FORWARD to eating it), I purchased two of the bigger size bags online (luckily they had a special FREE shipping going on at the time).

I am extremely satisfied with this grain free food.