Why are my chicken eggs not hatching?

The article was first published at backyardchickenscoop.com

Hatching your own chicken eggs can be more fun and exciting than picking up chicks from a store. It gives a tremendous experience to choose the eggs, incubate and track them to develop into fully grown chicks.

But, not all eggs hatch into a perfect chick. There are many reasons for the chicken eggs not to hatch. The following guide provides you the various causes for your eggs not hatching. You will also understand the reasons why eggs stop developing and how to check if an unhatched egg is alive or not.

In this article I will go through the following:

  1. What Causes Chicken Eggs Not To Hatch?
    1. Infertile Eggs
    2. Immature Breeder
    3. Immature or pullet eggs
    4. Undeveloped Egg
    5. Dead Embryo
    6. Inadequate Ventilation
    7. Inadequate Egg Turning
    8. Full Embryo Dead In Shell
    9. Chicks Smeared With Albumen
    10. Chicks Stuck In A Shell
  2. Why Do Chicken Eggs Stop Developing?
    1. Bacterial Infection
    2. Rigorous Vibration
    3. Deficiency of Nutrients
    4. Immature Embryo
    5. Choice of Nature
  3. How do you know if an unhatched egg is alive?
  4. How long leave unhatched eggs in an incubator?
  5. Can the chicken eggs hatch early or late than 21 days?


1. What Causes Chicken Eggs Not To Hatch?

You may be disappointed to see the chicken eggs fail to hatch even after incubating for weeks. When you know the reason for the eggs not hatching, you can prevent these issues in the future and get more successful hatch rates.


a. Infertile Eggs.

Infertile eggs are the primary cause of your eggs not hatching. Infertile eggs result from immature male or female chicken. It could also be from males with abnormal sperm or females with abnormal eggs.

Infrequent mating due to improper male to female ratio can lead to infertile eggs. Extreme weather conditions affect the formation of fertile eggs in the breeding stocks. The weather should neither be too hot nor too cold to form the fertile eggs.

Nutrition deficiencies and incorrect feeding of chicken can also lead to the formation of infertile eggs. Certain drugs or using pesticides on the crops that are fed to your chicken can be another reason for the breeders to lay infertile eggs.

The occurrence of diseases or infestation by parasites affects the breeders’ mating pattern. It leads to the laying of immature and infertile eggs.


b. Immature Breeder.

Breeder cock needs to be mature and in good health. Very young or old cocks have abnormal sperm count. This abnormality in their sperm count prevents strong, healthy and fertile eggs. Your breeder cock should be mature and have a near similar age to the hens.

Moreover, the hens in the breeding flock need to be mature and in good health to lay a sound and fertile egg.


c. Immature or pullet eggs.

The eggs selected for incubating should be in even shape and normal size with a strong outer shell. The first few eggs of a young hen also called pullet eggs are not recommended. They are small and immature eggs than those eggs that laid later. The eggs from very old flocks have a high degree of infertility. These types of eggs are not suitable for incubating and yield low hatching rates.


d. Undeveloped Egg.

Fertilized eggs with long storage periods or stored in extreme temperatures may destroy the live embryos inside the egg. Such eggs hatch with limited success and may not develop into a chick.

The eggs chosen for incubation needs to be handled with care during transportation. Rigorous handling of eggs results in intolerable vibrations that destroy the embryos inside the eggs.

When the incubation temperature is too high, it prevents the development of chick inside the egg or reduces the hatch rate. Sometimes it dries up the liquid albumen inside the egg by heavy water loss.


e. Dead Embryo.

A dead embryo inside a fertile egg does not hatch when the eggs are stored or incubated in extremely high or low temperatures. It kills the embryo of the egg and forms an infertile egg.

Rigorous handling of eggs during transportation, nutritional deficiencies or diseases in the breeder flock can also cause a dead embryo.


f. Inadequate Ventilation.

The eggs under incubation need proper ventilation for the embryos to nurture and grow. The incubator needs adequate ventilation to allow enough oxygen for embryos. The ventilator should let out the released carbon dioxide to allow fresh air to flow in.


g. Inadequate Egg Turning.

The inadequate or infrequent turning of eggs causes the embryos to get destroyed. The inappropriate turning of eggs leads to improper positioning of the embryo which leads to its death. You need to take the utmost care and caution while turning the eggs. It is preferable that you know how and when to turn the eggs.

Egg turning prevents the sticking of the embryo to the inner cell membrane. It stimulates the sub embryonic fluid and yolk formation. Hatching of fertile eggs is significantly better in eggs that are properly turned. It is not necessary to after 15 days of incubation.


h. Full Embryo Dead In Shell.

Maintaining a low humidity or low temperature in the incubator for a long period causes the fully grown embryo to die within the shell. Under these conditions, few embryos die even after they pip out of the egg.

High temperatures during the hatch, nutritional deficiencies and inadequate turning during the first 12 days of incubation also cause the embryo to die. Your eggs may not hatch without the proper turning into a full-grown embryo. The eggs need to be turned within the allowed frequency and time.


i. Chicks Smeared With Albumen.

Large eggs have high liquid albumen inside the eggs which gets slowly evaporates during incubation. When the humidity is high, it prevents the evaporation of the albumen leaving more water in the eggshell. This causes the chick to drown in the liquid in the shell. You can find a dried coating of albumen in the nostrils and beak that indicates the death due to drowning.

It is important to maintain proper humidity levels during the hatching time. Low humidity after the chick pips can stop the hatching process and prevents it further growing which causes the chicks to die.


j. Chicks Stuck In A Shell.

Poor quality or a cracked eggshell causes the chick to dry and gets stuck in the shell. The weak outer shell allows easy evaporation and quick-drying out of the liquid albumen inside the egg. Low humidity during incubation may further add to drying up of the cracked eggs.

Cracked eggshell gets stuck to the chick and causes it to die. Sometimes a little intervention by wetting the dry regions with spray or a wet cloth might help to remove the stuck eggshells.


2. Why Do Chicken Eggs Stop Developing?

There are many reasons for the fertile embryos to stop developing into a full-grown embryo. It primarily depends on the health and maturity of the eggs that can prevent such hindrances.


a. Bacterial Infection.

Bacterial infection of the eggs can occur if the eggs or the incubator are kept dirty. Bacteria transmits from the unclean surfaces into the egg. An unclean manual turning and candling also lead to bacterial infection and affects embryonic growth. You should ensure to have a clean and spotless incubating equipment and wash hands before turning of the eggs.


b. Rigorous Vibration.

Rigorous handling of the eggs during transportation makes the delicate eggs to shake and vibrate. This is the most common cause of early embryo death in the fertile eggs. Frequent and violent candling, turning of the egg by beginners also causes tremendous shake and vibration. You need to handle these eggs gently with mild movements to get better hatch rates.


c. Deficiency of Nutrients.

The death of the embryo is caused by the deficiency of vital nutrients such as Vitamin A and Vitamin E. Your breeding stock should be fed with good quality feed that can provide these nutrients to achieve the best hatching rates.


d. Immature Embryo.

Immature or weak embryo prevents the development of the full-grown embryo. It is important to ensure that your breeding stocks are mature, healthy and well-fed with quality and nutrition-rich food. You can avoid the formation of immature embryos in the eggs you choose for incubation.


e. Choice of Nature.

Sometimes it is simply the choice of nature to stop the development of the embryo. We have no control to enable the growth of the embryo in these conditions. The eggs do not hatch for the reasons beyond your control.


3. How do you know if an unhatched egg is alive?

You can check if the unhatched egg is alive or not by using the candling method. You need to flash a bright light right onto the egg in a totally dark environment. In a live egg, you can notice the chick moving around visibly inside the egg.

There is another tip to find if the chicks are still alive inside an unhatched egg. You can find a pink glow around the edges and a dark area in the center of the egg.

If the chicks are not alive, you can find the egg to be brownish and muddy inside the shell. You may not be able to find any movement of the chick when you pass the light.


4. How long leave unhatched eggs in an incubator?

You need to keep the unhatched eggs in the incubator for another 4 days after the main hatch period of 21 days. If the unhatched eggs that do not hatch on the 25th day, you need to plan to move the eggs away. A hen usually abandons the unhatched eggs after the incubation period.


5. Can the chicken eggs hatch early or late than 21 days?

Certain breeds of egg hatch early than 21 days when the incubation temperature is too high and the humidity is too low.

Eggs from older breeds are larger in size than normal eggs. These eggs have weak embryos and usually take a longer time to hatch. The low temperatures of the incubator can also cause a delay in the hatching of eggs.

The above guide provides you the different reasons why the eggs do not hatch even after 21 days of incubation. You also understood the reasons why your egg stops developing into a full-grown embryo. You had a brief idea of how to find if an unhatched egg is alive or not. These detailed causes, tips, and best practices help you to successfully incubate fertile eggs and get a high hatch rate of your chicks.