i'm sure a lot of you have seen something similar in text books
but we're just posting this to show you an actuall egg,,not a drawing
goose egg clearly shows what we consider to be ideal development
day 28 was marked in the morning and is mid way down the egg
the photo was taken at dinner time and the next morning this guy was ready to go to the brooder
if the air sack gets any bigger than this hatch rate suffers, and of those you do get to pip some may need some knid of assistance( mainly keeping the membrain wet so that the young bird doesnt get stuck and can move inside the egg)
we aim for the same development with our duck eggs
this year i sacrificed some duck eggs,a previous season had shown us what was too much air sac development, i wanted to know just how little development you could get away with and still get a reasonable hatch rate, line 26, which is the first line to the right of where the gossling is pipping is about as wet as you could expect to get away with,,if the development is any less than this, the hatch rate is poor, most of the duckling with less development than at line 26 pipped but did not hatch
the very first ring is 7 days from hatching,,from day one through to 21 the air sac development is very slow.
from what i've noted, even running the bator at 90% humidity you can't slow down the development of the air sac of a healthy chick in the last few days.
when we first started incubating we plotted wieght loss graphs and tried to follow those, unfortunately this method doesnt seem to work to well as the eggs end up being to dry. this method of visually tracking the air sac would be our recomended way of doing it
good luck and happy hatching
