I have a question....

[Heffalump]

So let's say I have a hen who lays an egg a day and can cover 10 eggs.

She goes broody and starts laying eggs.

By the time the first egg hatches would the last egg not be 9 or 10 days behind developmentally and so 9 or 10 days away from hatching?

Will the hen sit on her nest for that long?

Or what happens?

Can someone please explain, I can't wrap my head around it.

 

[featheredplanets]

They don’t lay while broody. They lay a clutch first then sit on them. So if hen lays 7 eggs and decides she’ll sit on them, she stops laying and sits on the eggs for 3 weeks.

 

[sourland]

Not all hens will go broody. A hen that goes broody will lay a clutch of eggs, and then she will start setting on them and lay no more eggs. That way all of the eggs will hatch at the same time. Other hens laying eggs in her nest will result in a staggered hatch which is generally disastrous.

 

[Heffalump]

Thank you both. That makes a lot more sense!

 

[Lady of McCamley]

A hen lays an egg about every 26 hours, so about an egg a day.

She lays, then gets up and goes about her business to lay again another day.

If her hormones are right (and haven't been selected out of her for egg productivity), she goes into a "pre-brooding" phase were she lays her daily egg, sits a few hours on the nest, but generally spends half a day foraging.

When she has a large enough clutch, anywhere from 6 eggs to 12, the pressure triggers a point on her breast bone that releases hormones from her pituitary that tell her to set. If those hormones are sufficient, she ceases to lay and sets. (With modern hens, the hormones are a bit funky, so she may lay for several days more even if she is setting, which will cause a stagger in hatch...a few days isn't a problem as that is something provided for later when the hen generally sits during hatching for about 2 days then raises up with her chicks to forage abandoning any un-hatched eggs).

A fertile egg only comes out of its stasis (arrested development) when it has been at about 100 to 102 degrees for 24 hours. (That's how she can sit a couple of hours, lay an egg, forage, and none of the eggs develop in the "pre-broody" phase).

So once she has sat a full 24 hours on the eggs, they "awaken" and begin to develop, generally at the same time, although those which have gotten the outer sphere of her body warmth may develop a little more slowly. She turns and rotates the eggs to hopefully evenly heat them.

So 21 days (22 after original set date), her chicks begin to hatch. Nature has provided each chick with the egg yolk drawn into their abdomen and sealed at the navel so they have food for about 2 days. This allows the slow hatchers and any eggs laid a day or two after start to finish and hatch.

At day 24 (2 days after the first hatches) the hen will take the chicks to a fresh location and to food and water. Any un-hatched eggs are abandoned.

So generally, she lays her clutch, sits for 24 hours to "activate" her clutch, then hatches her clutch which will normally stagger between 1 to 2 days in time, then gets up with the live chicks.

HTH
LofMc

EDITED to add, chicken eggs remain fertile for about 7 days after being laid, with about 10 days the maximum for viability. That means the first 7 eggs are generally the strongest and develop best. That also means some of the older eggs may have delayed development or simply not develop at all. Another reason for some of the staggering in the nest.

 

[Lady of McCamley]

And yes, I dealt with the hormones and process of one hen, however if she is in a flock, those laying eggs would be set at different times and would be at different development stages.

Which is why it is so important to gather eggs daily, mark date of egg when gathered, save eggs for a brooding hen in a dark carton, set those 7 days and younger, at the SAME time, isolating the hen or marking the eggs so additional eggs from the flock can be removed.

LofMc

 

[Heffalump]

A hen lays an egg about every 26 hours, so about an egg a day.

She lays, then gets up and goes about her business to lay again another day.

If her hormones are right (and haven't been selected out of her for egg productivity), she goes into a "pre-brooding" phase were she lays her daily egg, sits a few hours on the nest, but generally spends half a day foraging.

When she has a large enough clutch, anywhere from 6 eggs to 12, the pressure triggers a point on her breast bone that releases hormones from her pituitary that tell her to set. If those hormones are sufficient, she ceases to lay and sets. (With modern hens, the hormones are a bit funky, so she may lay for several days more even if she is setting, which will cause a stagger in hatch...a few days isn't a problem as that is something provided for later when the hen generally sits during hatching for about 2 days then raises up with her chicks to forage abandoning any un-hatched eggs).

A fertile egg only comes out of its stasis (arrested development) when it has been at about 100 to 102 degrees for 24 hours. (That's how she can sit a couple of hours, lay an egg, forage, and none of the eggs develop in the "pre-broody" phase).

So once she has sat a full 24 hours on the eggs, they "awaken" and begin to develop, generally at the same time, although those which have gotten the outer sphere of her body warmth may develop a little more slowly. She turns and rotates the eggs to hopefully evenly heat them.

So 21 days (22 after original set date), her chicks begin to hatch. Nature has provided each chick with the egg yolk drawn into their abdomen and sealed at the navel so they have food for about 2 days. This allows the slow hatchers and any eggs laid a day or two after start to finish and hatch.

At day 24 (2 days after the first hatches) the hen will take the chicks to a fresh location and to food and water. Any un-hatched eggs are abandoned.

So generally, she lays her clutch, sits for 24 hours to "activate" her clutch, then hatches her clutch which will normally stagger between 1 to 2 days in time, then gets up with the live chicks.

HTH
LofMc

EDITED to add, chicken eggs remain fertile for about 7 days after being laid, with about 10 days the maximum for viability. That means the first 7 eggs are generally the strongest and develop best. That also means some of the older eggs may have delayed development or simply not develop at all. Another reason for some of the staggering in the nest.

Thank you. Very helpful information.