What causes chicks to hatch with intestines out?

[Goat_Walker]

So at the fair they always have this incubator spot where you can watch chicks hatch.

When I went their was one with its intestines hanging out.

Tonight there are two different ones with the same problem. What causes this?

 

[purpletree23]

I could be wrong (and boy will someone let me know) but I think a lot of the hatching difficulties that happen with incubators is because they are malfunctioning somehow. The temp could be too high or low or the humidity could be off.

 

[emma121081]

I have had this problem with chicks in my incubator. If the bit hanging out is the yellow yolk sac it means the temperature in the incubator has nt been high enough for the chicks to develop correctly.