My 26 yr old mare has a big soft swollen area on her underbelly. It was not there yesterday but I noticed it right away when I fed this morning. She is acting normally and her appetite is good. Another mare had something similar this summer and the vet said it was summer edema. While this could be it, he said it was prevelant in overweight horses. This mare is not overweight, not a hard keeper, but not easy either. Any ideas? I hate to call the vet on a Sunday, so I thought I would post here first. Let me know if you are familiar with this one please!!