Hi and welcome to EBN. You can start by going to the Home Page and reading the Dog Food Ratings. It lists all the foods according to a Star rating from 6 Star down to a 1 Star, you want to choose a 4 Star or higher quality of food. A lot of Bullies are allergic or sensitive to chicken based foods, and also to grains, so try to choose a chicken and grain free formula. But every Bully is different and what works for one doesn't always work for another. It's really a trial and error process when trying to find a food that your bully will tolerate. A lot of members, including me feed their bullies Fromm's dog food. I feed our two guys the Fromm's Beef Frittata, as my female Blossom is allergic to chicken and salmon. When you are switching to a new food it is best to do a slow transition over two weeks so they don't get an upset stomach or diarrhea. Also it can take up to a month to see any improvement to or benefits from the new food, as it can take this long for the old food to leave their systems.
Hi and to EBN..... as for food, a grain free and chicken free food is a best place to start. Fromm, Orijen, Taste of the Wild, Nature's Instinct are some of the better lines to choose from