My last hatch involved co-broody hens (mother & daughter team). I joke that the serama sat on the eggs and the mod. game bantam sat on the serama. They are both very light and shared a few large orpington eggs, so no breakage issues. When the serama took a bio break was the only time the mod game got to sit on the eggs.
The hens did OK sharing the orpington & silkie chicks, but the serama hen hated the striped chicks (olive eggers) She kept attacking them! I added a brooder plate where the chipmunks could escape her wrath, but it became clear I had to split up the hens and divide their chicks.
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It goes to show that each hen is different.
My big beautiful blue orp is clumsy and often crushes her poor eggs. That 10.5 pound hen does better sitting on golf balls and then adding incubator chicks as they fluff up. After that point, she's a good mama and can cover a lot of baby chicks.
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