Yep-21 days, I have 24 eggs in the bator right now, due on April 7. for me, lockdown is april 5. I am keeping an eye on my silky mutt, as she is going to brood for the rest of the year for me.
We are not doing meat chickens this year, so I have to get my freezer full one way of the other. Once chickeneggs are done, the incubaotr will be used for quail the rest of they season.
I've never had a ful sized chicken go broody before, but as long as she is covering all of them and you can't see any part of egg sticking out from under her, she should be fine. I know my silkie mutt will only do 6.
My little Susie sat on 17 and 12 hatched. A BO can do 20 easy. Of course you could go and aquire some chicks and stick them under her when it is time, that is if you want to get a different breed than what you have.
If you want your hen to raise hatched chicks, I have found that letting them sit on eggs for at least 10 days is best. I did do one for less time last year and it did work. But I think you are taking more chances of the hen rejecting the chicks.
And yes it takes 21 days more or less. Susies chicks hatched over 5 days, I think.
You can also add chicks at the same time as yours are hatching, if you can get day old chicks of the breed you are looking for at the right time. The younger the chicks the better, although I have done it with 4 day old chicks.
I got lazy once and didn't collect for a week and my Faverolle was on around 20 easily. She's a broad girl. I don't have a roo so it was a huge waste of time for her but at least, I know who I'll use if I want more chicks.
It is really nice out and since I am puttering in the back yard I let the ducks out for play time and lawn mowing detail. But instead of 5 ducks running out of pen...there are only 4. Who's missing? Chrissy. Where is she? Usually she hangs back from the gate when everyone comes out because I am a big monster and might eat her ya know. But nope...she is not in the run. Then I look in the dog igloo and receive the notorious "broody stink eye" followed by the ever threatening wide open bill . Chrissy then proceeds to bury herself further in the straw just to let me know she is serious. Well OK then!
You go you insane little goober.
Now we are not sure if she is going to stick with it. If she does manage to set all day, I will give her the other 4 eggs I have in here that I was holding for a hatching egg order. I think she is on 5 now. Someone didn't lay yesterday morning, but I have had several days where I got 3 one day and 5 the next. Yesterday I only got 3.
If she stays on the nest I have to call my hatching egg customer and tell him I am not sure when his order will be ready. Hopefully they don't ALL go broody."