It all starts with the yolk, which is nothing more than a large chicken egg. And make it big! At about 4 centimeters in diameter, the hen’s egg is the largest in the animal kingdom. The yolk is released from the ovary and then “travels” through a series of internal organs of the penosa until it reaches the uterus, where the process of egg formation ends with the solidification of the shell. The total time for it to be ready is approximately 24 hours. “About 30 minutes after laying the egg, the hen ovulates a new yolk that will give rise to the whole process again”, says veterinarian Ismar Araújo de Moraes, from the Fluminense Federal University (UFF). The curious thing is that, when the hen is born, all the eggs that she will generate throughout her life are already stored in her ovary, only in microscopic size. Only in adulthood are they ready for ovulation. In a year, a hen lays about 265 eggs, and can maintain this production during the two years it has to live on a farm – if it is a hen raised in the garden, its life can be prolonged for about five or six years. All these dozens only become chicks when the painful mates with a rooster. “Rooster spermatozoa are quite resistant and survive up to 15 days inside the hen. During this period, she is fertile and the eggs will always be hatched (they can give rise to chicks)”, says the veterinarian. The yolk of a hatched egg has a small spot with a reddish ring, but it is difficult to differentiate with the naked eye.
– Why is the egg oval?
Put it out The longest step is the manufacture of the shell, which takes place in the womb and takes about 20 hours
1 – The formation of the egg begins in the ovary of the hen. It is in this organ that the eggs are found, which are nothing more than the yolks. Here, the eggs mature and incorporate a large amount of nutrients, such as mineral salts, proteins and fats.
Phase time – 0 h
2 – When an egg (yolk) is released, it migrates to a structure of the reproductive system called infundibulum. There the chalaza is formed, a thick membrane that protects the yolk and which will give rise to the white. It is also in the infundibulum that the rooster’s sperm fertilize the egg, if the hen has mated.
Phase time – 0h15
3 – The egg in formation then goes to the magnum, a kind of channel. The thick walls of the organ release substances such as proteins, sodium, calcium and magnesium, which complete the formation of the egg white, leaving it very thick, unlike what we see in a raw egg.
Stage time – 3h15
4 – Upon leaving the magnum, the egg goes to the isthmus, the last region of the reproductive system before the uterus. That’s where the egg white gains water and becomes fluid as we know it. The isthmus also forms the film that surrounds the inside of the egg shell.
Phase time – 4h30
5 – Inside the uterus, the egg receives a viscous mass, secreted by the mucosa of the organ. Such mass is the basis for the formation of the shell and solidifies after being impregnated by carbon and calcium crystals. This is the longest stage of the process, with the egg remaining in the uterus for about 20 hours.
Phase time – 24h30
6 – When the egg is ready, it goes to the vagina. It is expelled in a few seconds through the chicken’s cloaca, a chamber where the animal’s rectum and ureter, in addition to the vagina, lead. To prevent the egg from coming into contact with feces and urine residues present in the cloaca, the vagina protrudes outwards at the time of laying.