My chickens are dropping died over half the flock is died in the last 12 hrs. What the hell is going on? This is ten birds that were fine this morning and now died. They have no marks on them nothing. I have no idea what to do or if the rest are going to drop they seem fine. It's not the feed. The only thing I can think of is the dam duck. He gets the water nasty and i can't always get it cleaned up right away. But it is cleaned every day. HELP!!