A hen has a natural instinct to raise a family of chicks. There is a
hormonal change in her so that when she wants to raise chicks she will
loose some feathers from her breast so that more heat gets to the eggs,
sit on some eggs (although in reality these eggs may be fake,
infertile, or she may just sit on air), not get off that nest other
than once a day for half an hour so the eggs do not get cold, and peck
hard at anyone who tries to reach underneath her or get her off the
nest. If you do want her to raise chicks then you should put the eggs
that you want her to hatch and leave her for 21 days to incubate.
She should be away from the rest of the flock and in a nice dark and
cosy place with some straw or woodshavings to make a nest with and her
normal food and water. After she has raised the family and they have
left her at six to eight weeks of age she will no longer be broody.
However, if you do not want her to hatch out chicks then it is
necessary to break her up - to stop her from being broody. If you just
let her carry on doing this then she may sit on the eggs for 6 weeks or
more depending on how determined she is. Therefore, if we want her to
lay any eggs (hens do not lay eggs whilst they are broody) we must
intervene. To do this, we must cool her down and make it uncomfortable
for her to sit on the nest. I do this by putting her on wire mesh about
10cm above the ground so that air can circulate beneath her and the
wire makes it uncomfortable for her to lie down. The top and sides are
also open but I put an open umbrella over the top so that she has shade
and protection from the rain. She must also have normal food and water.
She will take about 1-3 days to stop being broody, depending on how
determined she is. Another method I have heard of but have never tried
is to stick a bag of frozen peas underneath her.