Egg-stepping is one of the breeding steps of poultry, and poultry all have extracorporeal intercourse.

It is not the eggs that are stepped on that can hatch the chicks, but the eggs that have been stepped on can hatch the chicks. Otherwise, the chicks cannot be hatched. The rooster steps on the eggs to help the hen hatch the eggs, so that the hen will lay eggs. The eggs can hatch into chicks.

The breeding method of chickens is to breed in large groups. A certain number of hens are matched with a certain number of roosters in proportion, so that each rooster and hen have the opportunity to mate freely. This breeding method has a higher fertilization rate, but it cannot determine the parents of the chicks, and is generally only used in breeding poultry farms.

Introduction to the reproductive system of chickens

The reproductive system of chickens is different from that of viviparous mammals. The testicles and epididymis of the rooster are in the abdominal cavity, the mating organ is a vestigial reproductive protrusion, and the sperm head is a long cone. Sperm can survive in the sperm gland nest in the hen's fallopian tube for up to 24 days and has the ability to fertilize.

The hen can ovulate once every 25 hours or so. Only the left ovary and fallopian tube develop. After the fertilized egg is discharged from the hen's body, its development will be suspended if it does not reach the critical level of hatching (24°C).