Dog and I went to close up barn shortly after dark. We were also to get eggs left in basket. Opossum about 2/3 grown was walking about in a pen. It was likely already stuff on most of the eggs in the basket. It was the fattest and furriest opossum I have ever seen. Dog walked over to it in no big hurry and sniffed from the side. The opossum fell over as if pushed over by the dogs nose. Opossum then played dead and dog walked off to check rest of barn. When the opossums growl or run the dog attacks. I dispatched opossum. Chickens could see opossum the whole time but made not alarm calls. They were used to it. One hen was a little fluffed up like when an owl visits, but only her.