hi my chicken sunny who is the largest hen and is at the top of the pecking order wont move that much! she started doing this about 3 days ago. I have to pick her up and put her in the roost my self because she isn't physically able to get up in the roost! she weighs almost 11 pounds! and she is just to fat. also yesterday and today I've noticed she doesn't want to move a lot. she just lays in the grass and pecks around also when she does walk around she wobbles and her tail feathers touch the ground as if it looks like shes constipated. whenever i go up to her she gets up and runs away but after she runs she slows down and pants a lot! what do i do?