We have some 10 month old Black Sex Link hens. There are 2 different pens of them but they are from the same group of chicks and are on the same field. In late December and early January we had some dogs to mess with our chickens. The dogs killed a few of the chickens and wounded some and the other chickens finished them off. They really terrorized this 1 pen over the other pen. We put an electric fence around the field and that kept the dogs away. But, since then we have had a pecking problem. All but 2 of the chickens in the pen have no feathers on their butts and a few have some missing feathers on their necks. We sprayed Blu Lotion on them to help deter pecking, it did help some. About a month ago 3 of the chickens started having this white sticky poop. We removed them from the pen. They act fine, very active. What causes this type of poop and what can we do for it. The other pen of chickens have none of these symptons. They are moved to new grass every day. They are on a hay field that has had no other livestock on it.