Will roosters fertilize all the chicken eggs?

* Egg Formation: A hen produces eggs regardless of whether she has mated with a rooster. The egg itself is formed in the hen's ovary and travels down the oviduct, where it receives its shell.

* Fertilization: Fertilization occurs when a sperm cell from a rooster enters the egg. This happens in the upper part of the hen's oviduct.

* Timing: For fertilization to occur, the rooster must have access to the hen and she must be receptive to mating shortly before the egg is released from her ovary.

In short:

* Unfertilized eggs: If a hen has no contact with a rooster, or if the rooster isn't around during the egg's formation, the egg will be unfertilized.

* Fertilized eggs: If a hen mates with a rooster, some of her eggs will be fertilized, but not all of them.

Here's a helpful analogy: Think of a hen's egg as a tiny room. The sperm cell needs to enter that room in order to "turn on" the embryo.