Weird eggs and oddities

The most common eggshell problems and laying abnormalities in our urban chicken coops!

Miniature eggs

These are small eggs the size of a large log that occur at the beginning or end of the laying period. They can indicate a pause. They often do not have yolks. It is only the white and the shell. This is also common during the sexual maturation of the hens. These eggs are impossible to fertilize, but they are edible.

Eggs with double yolks

When two yolks are released together in the oviduct, sometimes the white and shell can fit together and the result is a huge egg that can weigh up to 4.2 ounces. This type of situation rarely happens and although there should not be any problems, the hen should be watched, however, as she may have difficulty laying these large eggs and could die if the egg fails to come out. It is perfectly safe to eat eggs with double yolks. double yolkers. Watch this video of Lisa with this huge egg.

Spotted eggs

When the egg travels through the oviduct, it spins on itself and if it spins too fast, it could get a dark spot and look dirty. Conversely, if it turns too slowly, it could have spots of more colorful pigments. Welsummers species lay very nice eggs that are regularly spotted and completely normal. All these eggs are safe and can be eaten.

White spots and crusts

Very often, calcium deposits can settle on the shell and form a rough white crust. These are debris that reside in the oviduct during shell formation. This phenomenon is not a problem. Sometimes you can lift the debris with your fingernails, but these eggs are perfectly fine for consumption.

Wrinkles and furrows

Older chickens that are under intense stress, such as a dog chasing them, or barking very loudly, may lay wrinkled, furrowed eggs. Although these eggs may not be the most aesthetically pleasing, they are quite perfect for consumption.

Soft-shelled eggs

Soft-shelled eggs are usually due to a lack of calcium in their diet. However, there may also be other reasons such as a diet too rich in spinach. I wouldn’t risk eating these eggs because they lack the first protective layer, the antibacterial barrier. Throw them away as a precaution.

False eggs

One exception is to be considered with caution. They are extremely rare, but they often indicate salpingitis. The inflammation of this infection brings its share of internal materials such as pus. Although they look like eggs, they are not eggs. It is because the material travels in the oviduct that it takes this form. Often these hens must be removed. But before that, a visit to your veterinarian may suggest treatment. Do not eat these fake eggs.

Usually, odd eggs are produced occasionally and there is no need to worry too much about them, but it is always a good idea to refer to good sources of references, books, and our veterinarians. Do not eat the fake eggs.

Blood-stained eggs

Blood stains do not pose any danger. They are not a sign of a fertilized egg. Blood stains usually occur as a result of a ruptured blood vessel during the formation of the egg. Some breeds of layers lay more eggs with blood spots than others, but in general, blood spots are found in less than 1% of all eggs produced.

Deformed eggs

This type of egg may indicate a viral infection. They can also occur when old chickens are vaccinated for a respiratory disease. Occasional deformation, especially at the change of season, may be normal and due to the malfunctioning of the gland involved in shell formation. Most of the time, a hen that has been stressed or has flown higher and is shocked on landing or handled roughly could have its eggs deformed during their development. These eggs are safe to eat.

Abnormal APEX: Eggshell Apex Abnormalities (EAA)

In this figure, the eggs are not normal, they are called eggs with a glass ceiling.

The top, of the egg, the apex is deformed and recessed compared to the rest of the egg and it is very thin and fragile. This condition is associated with a Mycoplasma synoviaethe infection of the oviduct. Although treatable with antibiotics, the success rate is criticized. Do not eat these eggs.

Egg-laying abnormalities

Intra-abdominal laying

In some hens that ovulate normally, the yolk never enters the oviduct due to a malformation of the reproductive system. Hens with this defect usually have wet hindquarters. As a result, the yolks fall into the abdominal cavity where they are often absorbed, at least for some time, but not completely. This often results in an excess of fluid that makes the abdomen tense and hard to the touch.

These hens are unable to lay eggs and should therefore be removed.

Broken eggs in the oviduct

On rare occasions, the egg can break in the womb. Most of the time, the broken egg passes through without any problems, but sometimes it is not properly evacuated and an infection (peritonitis) may occur. The material is absorbed into the lung sacs and pneumonia may result. Often, it is not until the autopsy that a large amount of egg yolk is found in the abdomen. If more than one hen is affected by this problem, then bacteria may have affected your flock. This problem may be caused by a malfunction of the oviduct or the bronchitis virus. It could also be an Escherichia coli or Mycoplasma gallisepticum infection that produces a blockage of the oviduct.

Eggs without shells or hard-boiled eggs

Let us specify that they have nothing to do with the eggs with fragile shells which  are due essentially to the age of the hens, their food, and the conditions of the environment. The production of eggs without shells is quite frequent in dwarves whose size has been exaggeratedly reduced.

It is not rare to see a hen which the day before was in perfect health, presenting worrying signs of the kind: sickly aspect, pale or on the contrary purplish crest, ruffled plumage, hanging wings. One or two days later, after having evacuated the egg that was bothering her (often without shell, but sometimes normal), she regains her usual appearance, as if she had never suffered from anything. It is of course recommended not to use these hens for reproduction, in order to avoid multiplying the anomaly in the offspring. It is not recommended to eat them.

Abnormal retention

The retention of an egg in the oviduct provides a mechanical obstacle to the path of the eggs that were to follow, and the oviduct can become stuffed, distended, rendered absolutely inert. This case fatally leads to the death of the hen. At autopsy, the oviduct is found distended by a yellowish mass, as if cooked, formed of superimposed concentric layers, resulting from the imperfect elimination of the yolks that accumulate on top of each other. The mass in question can be the volume of an egg, a fist, or even two fists, resembling on the outside a real tumor.


Cloacal prolapse is a major disorder of the hen’s genital tract and one of the main causes of mortality at the beginning of laying. The hen’s cloaca is carried outward with its egg. This condition can be helped with a warm bath and lubrication of the cloaca. The onset of cloacal prolapse is closely related to exposure to light and reproductive hormones (estrogens, progesterones and androgens). It is therefore recommended to expose your hens to natural light every day. Some strains (especially white ones) or lines of hens are also more sensitive to this condition than others. During cloacal prolapse, the production of blood-stained eggs is often observed, as well as pericloacal inflammation. In severe cases, the exit of the intestinal coves or part of the oviduct is noted in the cloacal area.

Thanks to Peppercreek Farm Girl for allowing us the use of her photos.

Visit her Peppercreek Family Farms page on Facebook and on Instagram @peppercreekfarmgirl.

Thanks to Lisa Steele for her collaboration and permission to translate sections

Research, translation, writing: Louise Arbour

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