i did my first hatching of shipped eggs, i now have 9 out of 10, 5 week old, health happy chicks running around.
I could not see much with the aircell when i received them also. i let them sit for 24 hours before i put them in the incubator. They say the fresher the egg, the smaller the aircell.
My incubator also has them on their sides and it wasn't untill day 7 when i candled that i seen all 10 with saddle/detached aircells. They spent 7 days rolling around on their side.
I read on here about setting them upright, so i cut out egg cartons for each egg to sit upright. Pic below of my set up...
I continued on but was only tilting them twice a day because it looked like all 10 aircell where detached and i thought by only tilting them slightly (slight lean to the inside, then slight lean to the outside of my round incubator) to try and get the aircells to settle. I actually ended up leaving them upright to hatch, i did end up turning 1 on its side and it had a hard time hatching and died 12 hours after it finally hatched.
I would also suggest to put a tick on the side of the egg at day 7 candling to mark the eye and do the usually makes of the aircell, although i didn't do anymore markings of the aircells after day 7 due to detached aircells but did more regular candling to watch aircell development, mainly because i had to turn off the egg turned and do manual tilting.
good luck with your hatching,

for a high hatch rate
Keep us posted with you progress and cant wait to see your little chickies
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