So sorry for th delay in getting back to you. The breed is Buff Orpington. My first time incubating and it was AMAZING! So many emotions involved - it actually surprised me!
I attempted to hatch 5 eggs. 2 weren't fertile, 1 died while hatching (totally a beginners mistake - I'll explain ), and I ended up with 2 precious pullets!
As for the chick that I lost, the egg had an extremely small air sac when I candled for the last time on day 18. I'd read that if you hatch them with the air sac up right and in an egg carton, that can help prevent drowning. So....that's what I did. On day 21 my 2 chicks had pipped & hatched beautifully and I literally awoke out of a sound sleep in the middle of the night, was terrified thinking 'what if the egg/chick in the carton attempted to pip on the wrong end? He wouldn't make it because he'd be pipping into the carton!?!' I couldn't sleep, was in a panic and HAD to check, as we were heading into day 22. So, so sadly, when I gently lifted the egg and looked towards the bottom, I immediately saw an ENTIRE beak that had pushed completely through the egg , along with some feathers that were completely dry! I panicked, listened for life and felt/heard none so I couldn't help but gently open the egg in the event the little punkin was still hanging on. I peeled back the shell and the outer sac (?) and found a perfectly formed chick, yolk sac absorbed and all - he just couldn't push his way through the cardboard egg carton and died trying. It was awful! And still breaks my heart imagining him struggling! Ya live & learn I guess but this now really has me questioning if the hatching in the egg carton is the way to go when dealing with a small air sac. Any thoughts on this?
P.S. Sorry about the novel

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I just love this page!