I have 28 chickens in a tractor, all from different places. Added 7 Rocks last week, about 5 months old. The barred rocks (only the barred, not the buff or red rocks) of this group looked really sleepy the past few days. We thought it was cute... Until this morning, one was run over by the tractor because she wouldn't wake up-so, she is separated and hopefully her foot will heal- really don't want to put her down. When I checked on the rest this afternoon, another barred rock was dead. just dead! I removed her immediately. I am worried they are diseased and will kill the rest of my flock The only thing I can think of is that I also got another batch of 5 black copper marans and added them all with the rest on the same day. the marans don't act very "chickeny." one ameraucana/marans cross just sits all day. hardly moves. The others don't jump at the site of scraps like the others do. And the rooster doesn't act like a rooster, if you know what i mean. they were hatched in may, so he should be acting like a rooster I'm pretty sure. Could they have infected my chickens? The man who I got the rocks from is a friend and none of his are sickly. What do I do? I haven't noticed anything strange, except the sleepiness and that they are very small- but they are young so I don't know if that's normal. Thank you!