When chickens as a species first appeared on Earth, they were all like any other wild animal and didn't have much to do with humans. The most common chicken on everyone's table today is the poultry that humans domesticated from the original wild chicken. Although, all of the documented records of chicken raising in this country are more than 4,000 years old, that hasn't infected people like me who don't deal much with live chickens.

In our biology textbooks as children, we all learned that chickens are one of the representatives of oviparous animals, that their offspring complete their developmental process in an environment other than their mother's, and that the sources of nutrition all originate from the egg itself. Not all the eggs we see are the same; some of them are laid by hens without mating, while others are eggs that have been fertilized by roosters.

And not all oviparous animals, like chickens, can lay eggs without mating. The so-called "cuddly hens" are those that are guarding the chicks, or incubating the eggs. However, not all eggs can be hatched, because only fertilized eggs can be hatched by a hen.

The nature of oviparity - the fact that a hen lays an egg without mating does not mean that it can reproduce asexually

The so-called asexual reproduction is called reproduction only when it results in the creation of a new individual, and asexuality means that the mother reproduces herself without undergoing the process of fertilization and without involving the germ cells. It has just been hinted that unfertilized eggs can't hatch chicks when talking about the difference between fertilized and unfertilized eggs.

So such unfertilized eggs, which are unable to reproduce new individuals, cannot be called asexual, and certainly do not affect the way chickens are classified as oviparous. So what is an oviparous species? First of all, the offspring of such an animal is formed in the process of sexual reproduction, except that the fertilized eggs of its offspring develop outside the mother's body and eventually break out of their shells.

There are many oviparous animals, and in addition to today's protagonist, the chicken, most of the common birds, amphibians, and reptiles are oviparous. Whenever such reproduction occurs, it means that the species needs to expel fertilized eggs or eggs outside the body. What happens to those eggs, which are lapped into the environment, varies from animal to animal.

How are hens fertilized during mating?

In a hen's reproductive system, there is a special component called the spermatogonial fossa. This structure is responsible for the ability of the rooster's sperm to remain fertilized in the hen's oviduct for 24 days. The rooster's "coitus" is in a special place, usually hidden inside the cloaca.

The term cloaca may be unfamiliar to many people, but it also has another name, the **** cloaca. Its main functions are reproduction, urination and feces, and it is a cavity located at the confluence of the ends of the animal's reproductive, ureteric and digestive ducts. Not only does the chicken, an oviparous animal, have this structural component, but so do familiar birds, differing only in that both hens and roosters have this structure.

While the oviducts and ovaries form a major part of the hen's reproductive system, it is often the fully developed oviducts and ovaries on its left side that are capable of reproduction. Objectively speaking, both female, and male chickens have poorly developed and hidden sex organs.

When a rooster and a hen are mating, the hen usually adopts a full squatting, or semi-squatting position, with her shoulders raised upward by the support of her two wings. The rooster on the hen's back is mating, and the rooster's wings flap from side to side to maintain balance, not to fight as many people think.

Why can't unfertilized eggs hatch chicks?

First of all, we can distinguish whether an egg has been fertilized or not, the easiest way is to use a light bulb with enough light to shine on the egg to observe, if you don't know which side of the egg should be illuminated, you can rotate the egg's angle to observe, if the image is a little bit more, that is, we eat white boiled eggs knocked open the side of the side that has air holes.

As long as you see black shading on the egg, it's a fertilized egg that can hatch chicks. If you don't see blood on the yolk of an open egg or small black dots on the yolk of a hard-boiled egg, then the egg must not be able to hatch chicks; it's an unfertilized egg.

Whether an egg is fertilized or not determines its internal composition. Eggs may look simple, but they actually have complex components. The structure of a fertilized egg contains all the nutrients a chick needs before it breaks out of its shell, as well as the shell that protects it. An unfertilized egg does not have an embryonic disc; instead, it has a structure called an ovule.

Although, roosters will ejaculate up to billions of sperm counts (1.5 to 8 billion) in a single mating session, most of these are sacrificed during fertilization. The reason why technological tools like artificially inseminating chickens exist is to bring up the utilization rate of roosters. This is because, as long as the rooster does not ejaculate less than 100 million sperms, it will be able to achieve a good fertilization rate by means of artificial insemination.

Hens can't lay fertilized eggs all the way through the mating process, and the shortest time it takes for the first fertilized egg to be laid is usually about 25 hours, and the longest time is 139 hours, which averages out to about two days. Hens reach their peak fertilization rate on the second day and maintain 82% on the seventh day after mating. The shortest time a hen can be consistently fertilized is about 3 days, and the longest time is about 21 days, which averages out to about 12 days.

Of course, while hens can lay eggs all year long, most of those eggs are not fertilized. Hens don't have a lot of opportunities to mate with roosters and lay those fertilized eggs that can hatch chicks. Especially the chickens that are confined on large farms, if their purpose isn't specifically to lay fertilized eggs to hatch chicks, will likely not see a rooster for as long as they live.

Author: Shilan (plagiarism be damned)