Quick hatching questions (breed type)

[corvidae]

So we've been in lockdown a few days now and the chicks have been slowly hatching out, but I've noticed an odd difference that I wondered about. The Blue Andalusians that have been hatching are taking about 27-29 hours from pip to zip pretty consistently, and they've all hatched with either umbilical attachments or partial yolk sacs attached (which they've managed to rectify within a few hours of hatch with no ill effects noted). The Welsummers and OE's have all hatched with 2-4 hours from pip to zip, clean hatches. All of these eggs were incubated together, so completely same circumstances. Is this a breed difference? The Andalusians did start early (day 19), but even the ones hatching on day 21 (today) are hatching exactly the same way. Everyone so far has been healthy and happy, though the majority of the eggs remain unhatched at this time (8 out of 24 have hatched--not a huge sampling, but a definite noticeable difference).

Silly questions, manybe, but just a point of curiosity... Have you seen a difference in the way different breeds hatch?

 

[debilorrah]

I have had differences, but they are not breed specific. My last anomaly was a set of split lav ameraucanas. Candling on lockdown, I could clearly see that one would hatch late. And sure enough a full 24 hours after the last one out, during candling again, the egg peeped at me. That thing hatched in 30 minutes.

Ducks take forever to hatch. Silkies take forever to hatch. That is about all I have experience with.