I'm at a loss on what to do. I've bread chickens and turkeys for years but never had a issue like this. I ordered in some eggs on line as its the only way I could get new blood and barred rocks. The feedback wasn't geat and knew some eggs wouldn't hatch as they were far too small. My broody hatched 4 out the lot and usually get very good rates so that's the first disappointment. Now one by one in the breeding pen they have died off. The first was a few days old and looked like mum had done it somehow as it was dead in the dust bath. The second I found limp cold and barely alive and couldn't revive. 2 weeks old. Now today into my 3rd week another dead!! Only one left. Never had this before. The only thing I've done different is I suspected a poor or no hatch rate so bough chick starter from a local shop that had been decanted into small clear bags but no label. After they hatched I went and got a larger bag from my normal feed merchant which I started to feed a week ago. If the first was medicated and they ate that for a week but the second bag was not could that kill them off slowly? The second one had a lot of water coming up from its mouth. This latest one had food in its croup but not a massive amount. Cocci??(can never spell it but u know what I mean)