It definetely sounds like allergies, probably to the chicken, and I agree with the Purina, as being one of the worst foods. As a guideline you can check out the dog food ratings. We feed Fromms Beef Frittata to our guys, my female is allergic to chicken, salmon, grains and corn. Purina is listed as a 1 star and is full of grains, fillers, and chemicals and additives. A lt of bullies suffer from allergies, and sensitivities. Sometimes it's their immune system, and you can give them some supplements that will boost the I'm use system. We give our two guys plain unsweetened yogurt to their morning kibble, this provides probiotics and boosts the I'm use system, and also helps with digestion. We also give our guys salmon oil on their evening kibble, which provides Omega Oils, which is excellent for their skin, and coats, and rain, and we also add apple cider vinegar to their drinking water everyday. There are a lot of benefits to ACV, such as its a natural anti inflammatory, it kills the bad bacteria in the body, so boosts the immune system, and it also balances the Ph level of the blood. All of these are both natural and I expensive supplements so are safe for your dog, but very healthy and beneficial.