Hatching ducks

[ducksssss]

Could you guys tell me some hatching terminology like what
Zip
Internal pip
External pip
And any other things you can think of mean

 

[shicks0211]

Zip is when the chick has made a circular hole in the top of the egg. The internal pip is when you candle the egg and you can see the chicks beak has broken through the membrane and is peeping ..you'll see the beak in the air sack at the top of the egg. The external pip is when they've started breaking the shell.