Do chickens know which eggs are fertile and infertile?

[archeryrob]

We have a converted rabbit hutch I made into a brooder for a hen to raise chickens off eggs. I build a nesting box off the side we can access and we can access the chamber. The chamber has a hardware cloth floor and the water and food is on the far side. She comes out when we don't see her and eats and drinks and is back on the eggs. She craps and we break it up through the hardware cloth.

Today is 10 days into her sit. My daughter goes out to take care of the chickens and comes back and asks me if I broke any eggs over at the coop. Of course, it is a no. The sloped platform under the brooder had egg shells reminats on it. We checked the hen and she was only on 8 eggs instead of 12 eggs. There was not a sign of any egg or egg shell inside the brooder only where she couldn't clean it.

So, back to the question. Can they tell the eggs that are not developing and remove them from the nest? This hen literally crushed this eggs through 1/2" hardware cloth so there was not a sign of egg or shell inside the brooder. She is still acting broody and staying on the remaining 8 eggs.

I have never hatched using a hen, only an incubator. So this is new to me and I was surprised to find this. Obviously the eggs she destroyed were not fertile or there might have been some mass that wouldn't go through the hardware cloth? Making an assumption here.

 

[oldhenlikesdogs]

Yes, sometimes hens remove bad eggs. They feel different when they are developing.

 

[archeryrob]

She whittled the 12 down to 5 and three chicks have hatched. 2 on day 20, 1 on day 21. Now on day 23 and two eggs are still under her and I am wondering if the final two still have a chance.

 

[oldhenlikesdogs]

Generally on day 23 they are done for if they were all set at the same time.

 

[archeryrob]

So we can break them open, slowly, and see if it died and didn't break out or didn't form properly? Possibly just slowly developed?

 

[oldhenlikesdogs]

So we can break them open, slowly, and see if it died and didn't break out or didn't form properly? Possibly just slowly developed?

I always candle, than sniff the egg. If it's been incubate under a setting hen than generally they will hatch on day 20 and 21. I get rid of the rest on day 23 myself. If they stink I would not open it up, but otherwise you can.

 

[archeryrob]

My daughter broke the last two. One just had veins and did not develop. The one was fully formed but never broke the shell and died. It just lightly smelled, so I assumed it was good on the 21st day but didn't succeed in breaking the shell.

BTW, I can't smell crap, unless its a good one. Deviated septum with darn near broken noses and the Olfactories just aren't what they should be.