My 18 month old hen has gained a large amont of weight to the point of waddling like a duck & has not layed a egg in almost 2 months I picked her up & noticed her vent area is swollen no feathers & feels feverish. I'm very concerned none of the other hen have any of these symptoms .does anyone have any ideas of what this could be ? She still has a appetite & drinks a lot of water . Think could be worms or vent blockage?

