My baby and his diet

Question
My dog became very ill and I took him to the vet (vomiting and bloody mucus stool) and he started doing better with the different diet and medications.  He got ill again and I called the vet he said to watch his diet that he is eating something he is not supposed to.  I have 2 other dogs and give them all only dog food and dog treats and have been following them around most the time outside, so I don't get it.  Anyway, my neighbor was feeding him and I told him not to so that has stopped too, but now he has the bloody mucus stool.  I am watching him and will call the vet tomorrow, but I'm wondering if he just has a weak stomach and if there is a special diet I can put him on.  I am willing to cook the chicken and rice, and give him cottage cheese and such for life if need be and if it will help him.  I can tell when he is in pain as he runs behind the sofa and hides and it kills me.  Is there anything else that needs to be done (he had an x-ray, and antibiotics, and was given a penicillin shot on the first visit and given Flagyl).  Sorry, I know it said you wouldn't do detailed medical questions I only want a second opinion and want to look at diet.

Answer
Hi Amanda-

Was your dog diagnosed with HGE? I have a golden retriever who has HGE and he will have similar episodes every now and then where his colon gets inflamed and he starts vomiting and having bloody diarrhea. The fact that they put him on antibiotics is usually a clue that the colon was heavily inflamed and so they need to bring the swelling down.

My main question is going to be what brand and type of dog food are you feeding, and how often? What types of treats do you use? There is a large range of dog food, from foods made from very inferior grains and filler ingredients, to food made from all natural meat and vegetable with no grains.

I can tell you that my golden with HGE used to have episodes every month, and was always on stool softeners one week, then flagyl and imodium the next, then he would need an enema, then he would have a bloody outbreak. I was in the vets at least once a month with problems. That went on for a year until I changed his diet to a high quality, grain free all natural food, cut down on all his treats and his salt intake, and started using only home cooked boiled chicken and veggies as treats. Within two months I didn't have to use the stool softeners and other balancers and it has now been six months since his last outbreak.

If you could give me a little bit more about his diet, I may be able to offer some suggestions. Thanks!