Click screen to continue The Living Egg Story Click screen to continue

Chickens are one of the many animals around us that lay eggs. Some of these we eat. Others are special eggs that become chickens.

This is the female chicken called the hen. This is the male chicken called the cockerel or rooster. Can you notice some differences? For a chicken to grow inside the egg, the hen must first be mated with the rooster. The eggs she then lays will be fertile.

This is a fertile egg opened just after the hen has laid it. It doesn’t look any different from the normal eggs we eat, does it? Chickens don’t start to grow in the egg straight away. The egg needs to be kept warm before the chick will start to develop.

At the farm the hen would normally lay all her special fertile eggs in the nest. She would sit on them and keep them warm for 21 days until they hatched. We have put these fertile eggs in the incubator to keep them warm until they hatch. Let’s look at what happens inside the egg over the next 21 days.

After only 3 days of warmth from either mother hen or the incubator, our fertile eggs begins to change. Our chicken is starting to grow. Already the heart has started to beat. After 6 days the beak is starting to form and the legs and wings are too. Those lines are the veins carrying nutrients to the chicken for it to grow.

At day 9 the feathers are even starting to develop and the chicken is really starting to take shape. At day 18 the chicken is almost developed. The head is in the ‘air sac’ at the end of the egg, and it is breathing air just like we do. Over the net couple of days the chick will absorb the yolk into its body to prepare for the work ahead, when it begins to hatch.

The shell of the egg is beginning to crack The shell of the egg is beginning to crack. The chick is starting to hatch. This is called ‘pipping’. It takes quite a few hours for the chicken to hatch. It has to work very hard to break the shell. Eventually it does. It is very tired.

When the chick hatches, it looks very wet and soggy. Its feathers are covered in ‘dander’ which makes them appear wet. It doesn’t take long for the dander to fall off and the chick to become fluffy.

The chicken uses its ‘egg tooth’ to help break through the shell of the egg. The egg tooth is a hard lump on the end of the beak. Chickens only need the egg tooth to help them break out of the shell. Once they have hatched, the egg tooth falls off.

Once the chicks are fluffy and strong, they go into a brooder box Once the chicks are fluffy and strong, they go into a brooder box. This box has a light bulb in it to keep the chicks warm.   If the chicks were hatched in the nest, the mother hen would keep them warm until they grow up.  

Glossary of Terms Hen Female chicken Rooster Male chicken Chick Baby chicken Fertile egg Egg capable of producing a chick Yolk Yellow part of the egg, providing nutrients for the chick Air Sac Air bubble at blunt end of the egg Nest Where the hen sits to keep the eggs warm Incubator Controls temperature of the eggs Pipping First signs of the chick hatching Hatch Chick emerging from egg Dander Covering on down of newly-hatched chicks Feathers Outer covering of chickens Egg tooth Hard lump on beak to break through the shell Brooder House to keep chicks warm

Life Cycle