Has he been tested for EPI? I had the same issue with my rescue dog. Luckily he tested negative for EPI. His issue is food intolerance. He is now eating Royal Canin PV (potato and venison). He is absolutely thriving on that. Some people may bad mouth the Royal Canin brand but when your dog has a health issue you use what works. After a few months on this, when he had gained his weight, I gradually tried Natural Balance Venison and sweet potato, and that is working just fine too.
Studies were done that showed that many OTC single protein foods had other unnamed proteins in them. Thats why I felt it was important to start this process with an RX food to find what works.
