Odd situation

[n3kms]

I had had eggs in the incubator for almost a week when I had a pullet go broody. I was quite excited to her have raise my incubator chicks. She was sitting on two eggs. Before I got her moved she had gotten up and returned to the wrong nest box twice. I never thought they would continue to develop. Once I got her moved and settled about 4 days before due date, I put 2 incubator eggs under her with the others that she was sitting on. After I started adding chicks I took all eggs but one and put them in the incubator. All original incubator eggs hatched and chicks went under broody. There was an extra egg that had a blood ring and I tossed it but the two she originally had had continued to develop normally. One spent a couple of days in the incubator at high humidity the other had been under broody for those two days. I now have them in dry incubator in turner. I'm not sure when to lock down these two. Any ideas how to tell? I could try to candle frequently and look for internal pip but might miss it. There should be about a weeks difference in there due dates. April 1 was the incubator chicks due date. The first pipped on 19th day and the last was on the 21st day. Would her sitting on the wrong nest twice in pretty cool weather set them back some?

 

[lazy gardener]

I would candle them, and assuming that you can see inside them, put them into lock down when they are at the developmental stage that matches around day 18. (Air cell and chick size.) You'd be fine going into lock down any time after day 14, on the developmental scale, IMO. If the air cells are too small, hold off on increasing humidity until you see rocking, heer cheeping if you're at home to monitor. Otherwise, raise humidity at lock down and hope for the best. They've allready defied the odds, so... they're not quitters!!!

 

[n3kms]

I would candle them, and assuming that you can see inside them, put them into lock down when they are at the developmental stage that matches around day 18. (Air cell and chick size.)  You'd be fine going into lock down any time after day 14, on the developmental scale, IMO.  If the air cells are too small, hold off on increasing humidity until you see rocking, heer cheeping if you're at home to monitor.  Otherwise, raise humidity at lock down and hope for the best.  They've allready defied the odds, so... they're not quitters!!!

It's really hard to be sure on chick size they always seem pretty full to me the whole last week. I always second guess myself on air cell size as well. I always think they look small. But they easily look to be after day 14 and they should probably be due around the 8 so I f increasing humidity after the 14 th day is okay then I think I'll wait till tomorrow and lock down. I'm off work this week so I'll keeps close eye on them for cheeping between now and then. Out of curiosity, does anyone know how a hen increases humidity near hatch. Does thinking about taking care of all those babies or having to hold her bowels make her sweat? That last question was meant to be funny. But I really am curious about how it all works under the hen.

 

[WalnutHill]

I think the biggest factor in broody success is that their body heat is moist. What we create with electric heating elements is dry heat. So we have to add humidity to help compensate for what we take away with technology.

The broody, by definition, is moist heat. Her breast skin is like an armpit. She can provide cool fresh air by leaving the nest or raising her body, or warm moist air by setting more closely. Her nudging of the eggs (not really turning unless she steals them from another nest) helps keep them heated reasonably evenly.