Please consider grain free dog foods. The loose stools are a sign of discomfort for your dog. Imagine if you had to eat food that upset your stomach and you had loose stools. You would feel horrible. Your poor dog trying to hold it while you are at at work... your tummy would grumble. Discomfort!!!! I do not know for certain but I would bet it is the grain that is upsetting his stomach. You could try going grain free and see if there is a difference.
Once you go grain free you will never go back to the garbage foods out there. You will see an amazing difference in your dog. I have seen dogs behave better and feel better on a good quality dog food. These below might seem expensive is you are used to Purina or Pedigree but it is only about $2.00 to $4.00 per day. You can find them at Petco or Petsmart and even some grocery stores.
Calfornia Natural Grain Free
Blue Bufallo Wilderness
Taste of the Wild
Merrick Grain Free Dog food
Paul Newmans Grain Free
Pronature Holistic Grain Free
I think dogs are the most amazing creatures; they give
unconditional love. For me they are the role model for
~Gilda Radner (Saturday Night Live Actress)