Battery hens are vaccinated. Your roosters could have had a secret illness and the stress of moving brought it on to them. They could have also caught it from wild birds. Although I'm not sure if a hen being vaccinated means that they cant carry stuff...Does anyone have experience with battery hens spreading disease? Because I think I may have that issue.. Because 3 of the roosters I put the rescued hens with got sick, but none of the hens have gotten sick. 2 of the sick roosters recovered, but one had to be put to sleep today. Please PM me if you have had experience with something like that, thanks!
Hens go broody when you don’t want them to… and won’t go broody when you do. 
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