A hen lays around 300 eggs per year regardless of whether the eggs are fertilized or not. As with humans, ovulation takes place on a regular basis, and in the case of hens, this is almost daily. Occasionally, it is possible that on any given day two egg cells are emitted from the ovaries of a hen. The hen still lays just one egg, in such a case with a double yolk. Chickens may live to be several years old but their egg laying capacity rapidly diminishes after the first year, thereafter not even covering the costs of feed any longer. For this reason, these so-called spent hens are replaced by pullets (rearing chickens) after 1 or 1.5 years to be slaughtered and processed industrially.A hen’s laying activity may be interrupted by the so-called molting season to give it time to recuperate. During this period, a hen does not lay any eggs. It regenerates as it develops a new plumage. After the molting season, the egg-laying capacity and egg shell quality improve for a while.
