I have 2 week old chicks and they have started dying today. I woke up to find one dead, then went down later to find another laying on its side with its legs straight out, still breathing, so I picked it up and made it drink. it wouldn't eat, but would drink. It seemed okay, so I left, when I came back- dead. I sat watching them for almost an hour- now 2 more are dead and a few more are close. They start showing symptoms by opening their mouth then walking backwards and shaking their head, then they fall over and shake. I have been forcing them to drink water, the ones I have witnessed doing this I have quarantined for the rest of them. No bloody stools, but some are really loose. What do I do?