It has worked for me to let broodies sit on fake eggs, then order chicks for them to adopt. (It might take 2 broodies to raise one order of chicks, depending on what the hatchery's minimum is.)
When the chicks arrive in the mail, I put them in a brooder with a heat lamp to eat & drink that first day, then put them under the broody after dark that night. By morning, she and they have decided they belong. If it's a large number of chicks, I leave about half in the brooder for one more day, and put those underneath the hen on the second night (the hen seems able to cover more chicks when she's had a day to practice with live chicks rather than eggs.) Because it's only a day or two, the brooder does not need to be as big as usual for raising chicks, and they are still too young to fly out, so I can get by with a plastic bin or cardboard box a foot deep, paper towels for bedding, and they're out before it needs cleaning.
Yes, I've had some losses, but overall my success rate has been quite high, with a number of different hens and chicks.
This way probably takes more fussing than just putting the eggs under the hen, but it works with sexed chicks and with breeds that are not available as eggs. After the first few days, I don't see any difference between adopted chicks and ones that hatched under the hen.
If anybody can give me the cliff notes version, that would be much appreciated!
