We have had questions about whether it is possible to make a hen go broody, so we thought it was a great topic and worth sharing the information. Since this trait has been bred out of production birds, it is not as common for a hen to instinctively go broody. Concentration from large breeders has been to perpetuate meat weight and egg laying production, rather than broodiness that halts egg production for many weeks as the hen hatches the eggs and then raises those chicks.
To our knowledge, there is no sure way to encourage broodiness, but from our experience, if you leave a few eggs in the nest for a few days, a hen that is leaning toward broodiness will tend to get the urge to go broody. In the wild, the hen lays her eggs, then covers them to protect from predators and temperature fluctuations. If you see a nest of eggs covered you will also note a hen with a desire to go broody.
Heritage breeds such as Wyandottes, Cochins and Orpingtons are full size breeds that are most apt to go broody with little encouragement. The Buff Orpington and Cochin are far superior mothers over the Wyandottes. So if a Wyandotte does go broody and hatch the chicks you may want to remove the chicks to a prepared brooder to care for them. Be vigilant to be sure the hen does not abandon the chicks after they hatch. In small breeds, Serama, Silkies and Bantam Cochins are perpetual broodies and are often used for hatching a variety of eggs that are not their own. The problem with the small breeds is that they can only hatch a few eggs at a time, reliant on the size of those chosen eggs.
Mark the eggs so you can distinguish them from fresh eggs laid after those initial eggs. Also, mark your calendar so you have an approximate hatch date. The initial eggs left in the nest will be fine left there. If a hen were in the wild she would lay up to a dozen eggs which would take no less than two weeks or more before she actually sets on those eggs, so they will be viable at least that long.
Once a hen goes broody, you do not need to do anything except provide a quiet, undisturbed sheltered area along with fresh food and fresh water daily. Food and water should be nearby or she may not eat or drink. The farther from the nest, the less apt she will be to leave that nest. By nature she knows exactly what to do and exactly how to do it, without intervention, unless she abandons the eggs or the chicks. If she does abandon the eggs you can either slip them under another broody hen or place them in an incubator to finish the hatch.
Do not disturb her nest. The hen turns the eggs several times per day, and she will periodically leave the nest for food, water and to relieve herself, along with a quick dust bath on occasion, right up to day 18 of the incubation period. From day 18 to the average hatch date of 21 days, she will not leave the nest even to relieve herself until she determines that all have hatched that will hatch. Do not assume that on day 21 all eggs should have hatched. Mama hen will leave the nest when she is sure the hatch is complete.
Generally a hen that does go broody will also produce offspring more inclined to go broody at maturity. Our rare Landrace chicken breeds are inclined to go broody and are fierce protectors of their offspring.
If you are fortunate to encourage a hen to go broody, and if you must remove eggs to an incubator, make sure it is pre-heated and checked for proper temperature and humidity before placing the eggs pointed (narrow end) down, until day 18, then lay them down horizontally and patiently wait for the hatch either side of day 21.
When encouraging a hen to go broody, test with just a few eggs. When you are certain she is determined to brood, the proper number of eggs will be important. For a bantam breed, five or six eggs is the most they will be able to successfully handle, for Old English game or mid-sized breeds, nine or 10 eggs will be ample and for full size to large chicken breeds you can set up to 15 fertile eggs beneath her.
For further information on broody hens, refer to our article: http://www.backyardpoultrymag.com/how-broody-hen-hatches-chicks/.