I have been hatching out different batches of my Blue Copper Marans (usually only 3 or 4 chicks in each batch). All the chicks go to term but then all buy 2 have died before they are 5 weeks old. Some make it a day, some a week and some longer. I found the oldest one to make it so far dead this morning at 5 weeks old.
I had a couple that when born almost acted blind. They just stood there in the incubator or brooder just peeping extremely loud. They would not eat or drink on their own but if I put it on their beak, they would eat.
The ones that make it past the first couple days act normal in the brooder until all of a sudden one day, they would start fluffing out their feathers, keep trying to snuggle up to everyone else and their eyes seem to doze and they lose their balance. Other times, they would just stand under the heat lamp, and start rocking back and forth like they couldn't keep their balance and they would start to plummet forward and sometimes catch themselves, sometimes not. By the time I start to see those signs, it is always too late and within 12 hours, they are dead.
Any ideas why this is happening? I have other chicks in the box fathered by the same rooster that do fine and thrive. It seems to only be the chicks coming from the Blue Copper Marans hen. I did notice today that she probably has worms from what her poop looks like. Would that cause these problems? Can worms actually be passed on through the egg? Is it maybe an incompatibility between the hen and rooster?
Looking for thoughts....