Chickens Dying Unexpectedly

[Worried Hen]

Hi, I have three clucky Sussex chooks sitting on 10 eggs each. First hen has hatched 1 normal healthy chicken and 6 chickens are fully formed and fluffed up yet seem to be dying within 24 hours of hatching out. We never have had this problem before. Second clucky chook is having this problem as well, we have lost 6 again. We have eliminated that the hens are standing on the chicks. Can anyone help us?

 

[TOP KNOT]

check their navels, if the temp and humidity were off ( even with a broody) you can get open navels. They don't close completely in development. Its also called mushy chick disease or omohalitis.