I'm curious if anyone else's corgi has Exocrine Pancreatic Insufficiency? I searched the forums and didn't see it discussed anywhere, so I thought I'd pass our story along.
We discovered Kirby had it last year. He went from 33 pounds down to 22 pounds in about 3 months. His stool was very, very soft and he began eating it every chance he got, presumably trying to regain nutrients. The vets were unsure about the cause, trying different diets with no weight gain. Our vet had a conversation with an emergency vet at a nearby emergency hospital and they suggested testing him for EPI. The test came back positive. It turns out that his pancreas is not producing the enzyme necessary for proper digestion of his food. We've added Pancrezyme to his food with every meal, and we are happy to report that he is back to his old weight, and then some! He's stopped eating his poop too. It seems this problem is more common to German Shepherds and quite rare in Corgis. We were very afraid we may lose him and were grateful to the vets for discovering what is wrong. He needs to have the Pancryzme for the rest of his life, and it is expensive, $130 for a 12 ounce bottle which lasts 2 months, but it's well worth the price to keep him with us.
If we can help anyone who may unknowlingly have this issue, hopefully this helps.
The first 2 pictures are Kirby in July 2008, at his lowest weight right before being diagnosed. The 3rd one was in early December, looking quite plump and content :-)