If chicks are hatching early then your temps are off. You are getting birth defects from the temps hurrying along their development.
Get a new thermometer - a good model, not a cheap one. Regulate your temps in the bator over a periord of several days to a week before adding any more eggs.
You want eggs to hatch on day 21 - any sooner and you have problems like what you are seeing now.
Get a new thermometer - a good model, not a cheap one. Regulate your temps in the bator over a periord of several days to a week before adding any more eggs.
You want eggs to hatch on day 21 - any sooner and you have problems like what you are seeing now.