Hii have a chicken which has a huge swelling below her back end ,its about a large handfull in size and is very soft and quite warm to touch , we have treated it as if she where egg bound ,but its becoming apparent thats not the case ,she drinking loads and eating as normal,but does not move around alot as it must be quite heavy,it appeared over a week ,and she is about 7 months old ,also she has either lost or pulled out her feathers on her chest and lost all feathers around swelling ,we are running out of ideas other wise its off to vets ,any advice would be great thanks ,andy