They may have drowned. Do you hatch upright in cartons or do the earlier chicks play soccer with those still trying to hatch? I have had experience with chicks zipping along, getting kicked over (so beak is on the bottom) and having them drown. We hatch upright now. I'd also take a look at humidity (we go completely dry around 24% until lockdown at 65%).Good morning!
I'm hatching and went to bed with 4 marans eggs "unzipping". Instead of finding chicks this morning I found the eggs in exactly the same way. This hatch also included OE's (6 of 6 already hatched out by yesterday morning plus one BCM that already hatched fine). I took the chicks out and checked on the BCM's, thinking they had shrink wrapped or something.
3 out of the 4 were dead. Not dried out AT ALL. I "helped" the one that was still alive, even though he wasn't stuck. All of the dead chicks were completely formed, yolks absorbed, no blood, and up to halfway around the shell. I've never had that happen before. The only time I've had chicks die at that point is if they get stuck and dry out. That was not the case here. The one I "helped" seems to have his neck bent under if that means anything.
I have been doing consecutive hatches in my incubator. When I candled before lock down I noticed that the BCM eggs had much smaller air cells then the mixes. I just read somewhere that high humidity at first can make them 'die in their own slime'? So 6 of 6 OE's hatched and 1 of 6 BCM's (2 if you count the one I helped)??
Thanks in advance for any insight!