Ok glad u have a plan! I felt a need to ask since there was someone recently that had a broody setting on eggs of different ages (coincidently, i believe those eggs were 5 days behind same as yours), & that person did Not know what to do. And yay she is halfway there now on the first eggs! Wanna say this. From my personal experiences, when ive had a broody hatch eggs say 2 days later than the first chicks, the late chick(s) was not yet strong and mobile enough to keep up with the first chicks, who were rarin to go. Some chicks from broodies were sadly lost this way. Mainly because the chicks got left behind & grew cold in early morns after mama hen took her other chicks out to get food. I have Frequently put feed store chicks under broodies that have just finished hatching their own chicks. (A Great way to get desired breeds without having to deal with indoor brooders!) The feedstore chicks have been up to 2 WEEKS older than the broodys own chicks. I slip the older feedstore chicks in with mama the very first night after all her own chicks have hatched, before she takes any of them out of nestbox for first time & gets a good look at her brood. Have had 100% success rate doing it that way. The feed store chicks know where to find food and water. The new broody-hatched chicks meanwhile, can continue to gain strength and stay warm under broody. It has always seemed to me the broody is focused on the needs/activities of her chicks that hatched first, evidenced by fact broodies leave their remaining eggs after 2-3 days to tend to impatient chicks, even if the eggs left behind are still viable. (Since the broody didnt hatch the feedstore chicks herself, above rule doesnt ever seem to apply. She remains focused on the needs of (first) chicks she has actually hatched, The key is dont allow the broody to leave nestbox with chicks for first time until ALL chicks u want her to brood have been introduced at night. Some broodies have watched & seemed puzzled as to how the older feedstore chicks are so smart!, but still 100% acceptance rate.
) I am going to assume your broody will be a great first-time mom,. But from my past experiences, she wont understand that the chicks that hatch 5 days later need time to gain strength to keep up. I have found 2 solutions to above problem that have both worked for me. 1) Remove the earlier chicks that hatch, put them in a,temporary brooder with heat, food & water. When late eggs have all hatched, Then slip the early chicks in with mom and younger chicks at night. 2) Keep the living space for broody & all the chicks very small and contained until youngest chicks are 24 hours old or so so they have sufficient strength. That way the broody wont be able to leave the youngest chicks behind, & they can stay under her for warmth. Even still, i foresee a potential problem for u re plan #2. After 5 days with her first chicks, i think it is LIKELY the later, younger chicks will be rejected, since your girl will have already bonded with the early chicks. I have have dealt with that issue too, ranging from a broody outright killing the perceived introduced "intruder" chicks, to making the introduced "intruder" chicks stand in a corner without warmth, food or water til their "real" mom comes back. (I ended up having to artificially brood that feedstore bunch). Since these are my(numerous) personal experiences only, i am hoping others will give u additional input. Even if u need to ask the question in a seperate thread, i think its a very impirtant question, and would be good to get input from others asking if they think your original idea will work.
Sending positive waves!
