Recently my neighbor, who's chickens I envy, had her 4 mo faverolle chick layed up with illness. It was first thought the chick had lost weight due to being lowest on the pecking order and not having access to dinner. When she was quarantined with her own food, however, it was found that she was actually suffering from worms, probably roundworms.
That sent us all into action, putting me on the line to my own vet-sister (don't you envy me now?) who instructed us both to WORM ALL CHICKENS.
My current coop consists of eight 4mo chicks and Twyla, the cranky (we call her demented) Swedish Flower with bad broken feathers and a bad disposition. Twyla was the most beautiful when she came home with me, unfortunately the other hens never understood her and she was hated for her beauty. They abused her to the point where I thought she would be killed off. Because of this she was banned to the chick pen. As fate would have it, a mink entered the henhouse and killed the other chickens, she was left to dominate the chicks. She has only been laying once or twice a week lately and I chalked it up to having to spend time in the path of frenzied buckeyes who are now bigger, but still dumber, than her.
Last Sunday was dosing day, and wouldn't you know she's layed every day. Too bad the eggs have to be discarded, and I'm hoping she's not doing this just to spite me. We'll see how well the rest of her improves, she was quite the beautiful hen back when her feathers were good.