How Do Eggs Get Fertilized?

Most women are able to become pregnant from puberty, when their menstrual cycles begin, until menopause, when their cycles stop. A pregnancy starts with fertilization, when a woman’s egg joins with a man’s sperm. Fertilization usually takes place in a fallopian tube that links an ovary to the uterus. If the fertilized egg successfully travels down the fallopian tube and implants in the uterus, an embryo starts growing.

When a fertilized egg does implant, a hormone called human chorionic gonadotropin (hCG) begins to be produced in the uterus. Other signs such as breast changes and nausea occur in a woman’s body, also meaning that pregnancy has begun.

How do chicken eggs get fertilized?

Hen eggs are not fertilized when they are laid. For a hen to lay fertilized eggs, she needs a rooster. … He must mate with the female hen so his sperm travels into the oviduct and fertilizes the eggs that the hen lays in the next few days.

How do farmers know if a chicken egg is fertilized?

If you want to know if your egg has been fertilized, crack it and look for the blastoderm — a white spot on the yolk, or maybe even blood spots. … Fertilized eggs will have dark splotches in them, or might be entirely opaque, depending on the stage of development of the chick.

Are the eggs we eat fertilized?

Most eggs sold commercially in the grocery store are from poultry farms and have not been fertilized. … Given the right nutrients, hens will lay eggs with or without having been in the presence of a rooster. For an egg to become fertilized, a hen and rooster must mate prior to the formation and laying of the egg.

Hen eggs are not fertilized when they are laid. For a hen to lay fertilized eggs, she needs a rooster. The rooster will fertilize the eggs of up to 10 hens. He must mate with the female hen so his sperm travels into the oviduct and fertilizes the eggs that the hen lays in the next few days. If you are looking to expand or maintain the size of your flock, you will need a rooster and you will need to ensure that your hens and rooster are mating.

In some cases, there is no courtship or ritual, and mating between the rooster and a hen can be aggressive, leaving the female with injuries. Colorful and large combs and wattles are also considered highly attractive to females.

Secondary roosters do still mate with hens, but it takes more effort and they do not usually get the pick of the flock. Even with the ideal ratio of males to females, it is not unusual for a rooster to have one or two favorite hens: ones that he returns to in preference to others in the flock. The hen must extend her cloaca so the sperm reaches the waiting eggs.

Once the mating process is complete, the rooster will usually walk away and the hen will collect herself and carry on. The amount of sperm that they produce will diminish as they age, but a rooster will normally remain active for several years. Image Credit: JollyX, Shutterstock The simplest way to check if an egg is fertilized is to open it.

If the hen is productive and the sperm remains viable for two weeks, however, a rooster could fertilize 14 eggs from a single mating. Roosters are sexually active from several months after birth, and it is their job to ensure the survival of the flock by mating with hens and fertilizing eggs. The rooster will hop on the hens back and perform a cloacal kiss, delivering sperm into the oviduct.

Nicole is the proud mom of Baby, a Burmese cat and Rosa, a New Zealand Huntaway. A Canadian expat, Nicole now lives on a lush forest property with her Kiwi husband in New Zealand.

Courtship, mating, and raising brood starts in the springtime. The increase in daylight energizes the hormones, and the increase in hormones leads to procreation behaviors.

A rooster is genetically programmed to take the task of populating the world with his offspring, and he is single-minded about it, dedicated even! The pineal gland in the chickens brain detects the increase in light this, in turn, stimulates the manufacture of androgen, estrogen, and progesterone the hormones responsible for increasing egg production and broodiness.

You should remember that many of todays chicken breeds have had the innate ability to become broody bred out of them, so few, if any, will sit on eggs for you. Most of these secondary brooders will not sit for 21 days, so placing eggs under them is probably a waste of time, but occasionally one will see it through! Its a bit like a rooster tango he will approach the hen from the side, dropping a wing near to the ground and do a little fancy footwork around her.

A Nicely Combed / Wattled RoosterHe will start tid-bitting in earnest once spring arrives. He will pick up interesting morsels for the hen to inspect, luring her over to check it out. If it turns out to be nothing of interest to the hen, she will brush him off, so he must be on top form in several arenas of showmanship and ability to win her approval.

If you are witnessing a mating for the first time, you can be forgiven for thinking its more akin to rape than love, but fortunately, the hens dont see it that way. The act of mating looks quite barbaric but, in fact, rarely results in serious injuries. A rooster can adequately cover up to around 15 hens, but in reality, he likely will have favorites that he will tend to more frequently.

Once the hen has decided she will accept the rooster, she will squat down to the ground and spread her wings to steady herself. He will mount her from the back, grabbing her head feathers in his beak and treading her with his feet to find a stable spot on which he can balance. Her sides can be ripped by claws or long spurs, causing some skin to be torn up.

Once he maneuvers into position, the hens cloaca averts as does his, resulting in a cloacal kiss. His sperm is transferred from his papilla to the hens vagina, beginning its long journey. Sperm from the rooster is deposited in the hens cloacal area and migrates up into the vagina, where it can rest in pockets in the wall.

Rooster sperm is viable for 7-10 days inside the pockets, although fresh is best. However, sperm intent on fertilizing travel on up into the area of the oviduct known as the infundibulum to ensure success. It takes about 5 hours for cell division to start, and at this point, it is called a blastoderm or embryo.

If our hen is interested in being a mother, she will now find herself a nesting place that is quiet and dark. Firstly, make sure the rooster cant hurt her during mating trim spurs and talons; use a hen saddle if necessary. Secondly, when she is looking for a dark and secure place to set, try to encourage her into a small separate area where she can be undisturbed by the other birds.

They will learn all they need to know from her, and if the rooster is a family guy, he, too, will take turns looking out for his offspring.

Here, well talk through what different parts of the body are doing at different times to prepare for pregnancy when it occurs from penis-vagina sex or from other forms of insemination, such as artificial insemination. Some of this information might also apply to conception that happens with the help of artificial reproductive technologies (like in-vitro fertilization (IVF)), though we don’t directly focus on that topic here.

Be prepared: bodies, sperm, and eggs do a lot of work to achieve a pregnancy. Also, FYI, a lot of this information is based on animal research, especially events that happen deep in the reproductive tract.

Before diving into conception, you should brush up on your knowledge of eggs and sperm , and of how ovulation works . Between your period and ovulation: As estrogen levels rise, the amount of cervical fluid increases and becomes wetter, thicker and cloudier (2,3). Around ovulation: Cervical fluid often looks like egg white: its thin, slippery, and stretchy (2-4).

If this fluid is absent or is thick and sticky, sperm have a hard time passing the cervix (3,4). The time period between when cervical fluid is ideal for sperm and ovulation is known as the fertile window . During your period , the uterus sheds the endometrium, which built up during the previous menstrual cycle.

Estrogen causes the lining of the uterus to thicken by stimulating the endometrial cells to divide (2). Also, the rise in progesterone after ovulation also signals to the endometrium to release little sugar-filled sacs into the uterus to nourish the incoming egg (2). If a person has unprotected penis-vagina sex during their fertile window, probably at least some sperm will make its way through the cervix and into the uterus.

(With artificial insemination, sperm is often introduced directly into the cervix or uterus, so this step is bypassed.) Sexual activity can cause the brain to release the hormone oxytocin (1,6), which causes the innermost layer of the uterus to contract and push the sperm onwards (1,5,6). The uterus also has little finger like structures called cilia that help move the sperm, hopefully, towards the egg (1).

Only a tiny fraction of the sperm that entered the vagina make it to the fallopian tube (5). Progesterone and estrogen influence this process by increasing the number of cilia and how fast they move (1). As they travel through the fallopian tubes, sperm gain the ability to fertilize an egg (1).

Although its come so far and has already changed, the sperm still has work to do: specifically, breaking through the barriers around the egg.

Dominant Roosters

During springtime, roosters are more active in their mating quest. At this time, they may exhibit courtship patterns.In some cases, there is no courtship or ritual, and mating between the rooster and a hen can be aggressive, leaving the female with injuries.

Secondary Roosters

Secondary roosters do still mate with hens, but it takes more effort and they do not usually get the pick of the flock. Secondary roosters will have to rely on tricks like tidbitting to pick up a hen.

Favorites

A single rooster will usually service around 10 hens. Any more than this and he can become stressed trying to manage the hens. Any fewer and the hens can become battered and overworked.Even with the ideal ratio of males to females, it is not unusual for a rooster to have one or two favorite hens: ones that he returns to in preference to others in the flock. These hens can become over-used. They may have damaged skin and show a loss of feathers around the back and neck. Hen saddles can be placed on the favorites to prevent this damage from occurring.

Preparing

The actual process of mating is relatively quick. Once any courtship has been completed, the rooster will hop on the hen’s back. If the female is compliant, she will squat and drop her head and body. By also spreading her wings, she is showing her willingness. The male will tread to help him get balance and will usually grab the comb to further steady his balance.

The Cloacal Kiss

Once the rooster is in position, he drops his tail down and delivers a cloacal kiss. A rooster does not have a penis, but rather a bump inside the cloaca called the papilla. This delivers the sperm. The hen must extend her cloaca so the sperm reaches the waiting eggs. The sperm will fertilize the day’s eggs, and some will also collect in sperm pockets, from which it can fertilize eggs for the next four or five days.Once the mating process is complete, the rooster will usually walk away and the hen will collect herself and carry on.

What Age Do Roosters Start Mating?

Cockerels usually reach sexual maturity at the age of 4 to 5 months of age. At this age, they will usually produce sperm and start to act like roosters. The amount of sperm that they produce will diminish as they age, but a rooster will normally remain active for several years.

Why Do Chickens Run Before Mating?

Sometimes, when the hen does not want to mate, she will run away. The rooster will chase after her, hold her down, and mate her.

Spring Fever – Mating Season

Courtship, mating, and raising brood starts in the springtime. The increase in daylight energizes the hormones, and the increase in hormones leads to procreation behaviors.The pineal gland in the chicken’s brain detects the increase in light – this, in turn, stimulates the manufacture of androgen, estrogen, and progesterone – the hormones responsible for increasing egg production and broodiness.These hormones, in turn, produce a cascade of other hormones necessary for the development of the yolk and the soon-to-be embryo.You should remember that many of today’s chicken breeds have had the innate ability to become broody bred out of them, so few, if any, will sit on eggs for you. If you don’t have a broody hen, you will certainly need an incubator.An interesting thing to note here is that broodiness is ‘infectious.’ If you get one hen to go broody, you will likely have at least one more of the ladies who want to brood!Most of these ‘secondary’ brooders will not sit for 21 days, so placing eggs under them is probably a waste of time, but occasionally one will see it through!

Chicken Courtship

Some roosters are a little bit romantic – others not so much. To indicate interest in a particular hen, the rooster will perform the courtship dance.It’s a bit like a rooster tango – he will approach the hen from the side, dropping a wing near to the ground and do a little fancy footwork around her.This is his ‘come hither dance, and he will repeat it until she either indicates she likes him or walks away from him.Hens’ are no easy mark, though – they will have evaluated his merits as a suitor. Does he provide food? Is he a good protector? Is he healthy?And is he sexy? (a red comb and wattles really get the ladies interested). If he passes the inspection, she will let him mate. If not, she will ignore him.He will start ‘tid-bitting’ in earnest once spring arrives.He will pick up interesting morsels for the hen to inspect, luring her over to check it out.If it turns out to be nothing of interest to the hen, she will brush him off, so he must be on top form in several arenas of showmanship and ability to win her approval.Occasionally, a hen will dislike the rooster and may never mate with him at all, but this is rather unusual.Hens also have a neat little trick about rooster sperm.If they decide they don’t want the sperm from the mating, they can eject most sperm to avoid fertilization.

Mating

If you are witnessing a mating for the first time, you can be forgiven for thinking it’s more akin to rape than ‘love,’ but fortunately, the hens don’t see it that way.The act of mating looks quite barbaric but, in fact, rarely results in serious injuries.He can mate anywhere from 10-30 times per day depending on the level of co-operation from the ladies.A rooster can adequately cover up to around 15 hens, but in reality, he likely will have favorites that he will tend to more frequently.The optimum time for mating is early morning, when his sperm load can be anywhere betweenOnce the hen has decided she will accept the rooster, she will squat down to the ground and spread her wings to steady herself.He will mount her from the back, grabbing her head feathers in his beak and treading her with his feet to find a stable spot on which he can balance.He will use his claws to get a steady grip on her – this is where most injuries to hens occur. Her sides can be ripped by claws or long spurs, causing some skin to be torn up.You can help the hen to ensure that the roosters’ spurs are short and if he is frequently mating with certain hens, fit them out with a hen saddle for protection.

Chicken Reproductive Anatomy

The mating act is very brief. Once he maneuvers into position, the hens’ cloaca averts as does his, resulting in a cloacal ‘kiss.’His sperm is transferred from his papilla to the hens’ vagina, beginning its long journey.The mated hen will shake out her feathers and go about her business as if nothing happened – so much for love.

The Journey

Sperm from the rooster is deposited in the hens’ cloacal area and migrates up into the vagina, where it can rest in ‘pockets’ in the wall.Rooster sperm is viable for 7-10 days inside the pockets, although fresh is best.However, sperm intent on fertilizing travel on up into the area of the oviduct known as theThe hen’s oviduct is approximately 30 inches long, and the intrepid sperm travels about 29 inches to reach the infundibulum and deliver the genetic code to the germinal disc of the egg.Once the rooster DNA is delivered to the hen DNA in the germinal disc, they fuse and become a zygote (fertilized seed).It takes about 5 hours for cell division to start, and at this point, it is called a blastoderm or embryo.This includes laying down albumin, building the shell, and applying the bloom before the eggs lay.She will start to cache her eggs until she has enough to start incubating them.If she has too many, remove some to another hen or incubator.

Development & Brooding

If you allow the hens to hatch their own, you can do a few things to make the process smooth.Firstly, make sure the rooster can’t hurt her during mating – trim spurs and talons; use a hen saddle if necessary.Secondly, when she is looking for a dark and secure place to set, try to encourage her into a small separate area where she can be undisturbed by the other birds.Add in a feeder and waterer, so she has her own little ‘apartment,’ and she should be all set. The area should, of course, be fully secured and be locked down for safety overnight.Once our hen has decided she has enough eggs to sit on, she will start to brood. This means she will sit on those eggs for the next 21 days until they hatch or die.She will chase off the rooster if he tries to mate with her at this point.Once she becomes fully broody, the rooster will not fuss with her. He may be a Mr. Nice Guy and sit on her eggs for a while, but most roosters don’t. His involvement with the chicks will not start until they are hatched.Our broody will diligently turn, warm, and fuss over her eggs for the next 21 days. During that time, she will rarely leave the nest.You may see her once a day run out to poop, perhaps have a quick dust bath and then run back to the nest where she will rearrange her eggs before sitting again – total dedication!

Hatching

Once hatched, Mama will take great care of her little chicks. No one will mess with a broody hen and chicks – she will defend them most vigorously.They will learn all they need to know from her, and if the rooster is a ‘family guy,’ he, too, will take turns looking out for his offspring.Here is a complete guide on raising chicks once they have hatched.

Sperm try their best

During your period, the uterus sheds the endometrium, which built up during the previous menstrual cycle. After shedding, the endometrium waits for estrogen (produced in the ovaries) to rise. Estrogen causes the lining of the uterus to thicken by stimulating the endometrial cells to divide (2).After ovulation, the endometrium prepares for the possible arrival of a fertilized egg. In response to increasing levels of progesterone:Also, the rise in progesterone after ovulation also signals to the endometrium to release little sugar-filled sacs into the uterus to nourish the incoming egg (2).

When does a pregnancy officially begin?

When the uterus detects the blastocyst, it releases enzymes to break down the blastocyst’s outer membrane.Once that barrier is broken down, the blastocyst can attach to the endometrium (1).This is when a pregnancy officially begins.