5. Find a dog food that has bacteria cultures in it. The same kind of cultures that are in yogurt. These"good bacteria" help dogs with their digestion and keep them h Best Canned Dog Foods ealthy. These will help to give your dog a healthy GI tract and in turn more nutrients will be absorbed.6. Stay away from any dog food that has chemical preservatives in it especially BHA, BHT and ethoxoquin.7. A high quality dog food will alway have vitamins, minerals and antioxidants added to them. Grape seed extract is also beneficial to boost the immune system.