Why Hens Lay Weird Eggs

Reading Time: 6 minutes

Weird eggs are all part and parcel of owning chickens, but which egg oddities should cause concern, and which are incidental? Hens tend to pitch us a curveball in the nesting box once in a while, but not all of these weird eggs are cause for concern. Let’s look at a few common egg abnormalities, and I’ll explain why they happen, and what they mean.

Weird Eggs

Some egg abnormalities are external egg flaws, some are internal egg flaws, and some aren’t even eggs at all. Most times you see an abnormality in your eggs, you can likely attribute it to the hen’s environment. High heat, humidity, crowded coops, loud sounds, and other stressors can cause many of these weird eggs.

Fart Eggs

When young pullets start laying eggs, you may find a “fart” egg or two. A “fart,” “wind,” or “dwarf” egg is just a shell and some albumin, sans the yolk. Pullets sometimes produce one of these eggs when their immature reproductive tract is just beginning to function. Don’t be alarmed; they’ll get the hang of laying a real egg soon.

Oversized Eggs

Hens are very sensitive to light duration. Typically, it’s suggested that you supply sixteen hours of artificial light in your coop that coincides with natural daylight. Sometimes, either due to incorrect settings, power outages or timer malfunctions; the artificial light changes suddenly. If you notice a large number of oversized eggs suddenly in your flock, check your lights. Disturbing the lighting scheme in a coop can be dangerous, even deadly to high-performance birds, especially commercial birds like Leghorns and Sex-link egg layers.

Bloody Shells

If you find blood on your eggshells, it likely came from the vent of the bird that laid it. When a young hen starts laying, you may see some evidence of blood staining. Blood staining can be expected while the hen’s reproductive tract matures and the vent becomes more pliable and hardly worth concern.

In a mature flock, blood streaking may indicate that your hens are laying a larger than usual egg. These larger eggs may be the natural progression and aging process, or it may signal a lighting issue. Blood droplets on eggshells are a more significant concern. If you see a bloody egg that is more than a little red streaking, check to be sure that you don’t have a prolapsed oviduct or a victim of cannibalism in the flock. In either case, these birds need to be separated from the flock for their protection and cared for separately.

Mended Eggs

Sometimes a hen has an egg break while it forms inside her. When this happens, the reproductive tract can mend this egg, but they will be deformed. These malformed or mended weird eggs are usually due to overcrowding or a physical force, like a fall or physical strike to the hen’s body.

Hairline Cracks

Small hairline cracks are very common, especially in older flocks. Heat stress and age are the more common reasons you see cracks when you candle eggs, but it may be a nutritional issue. Things like mycotoxins, low trace elements (vitamins and minerals) and insufficient free calcium may cause these cracks to form. If you have a lot of weird eggs with hairline cracks, be sure you’re feeding a good layer feed and try to reduce the heat in your coop during the warm months.

Wavy Or Creased Eggs

Eggs spin in the reproductive tract as they form, but when birds are stressed out, they can produce one of these weird eggs. Older hens are more prone to this, and it may be something as simple as heat stress. If you see a lot of wrinkled eggs, you should be on the lookout for sick birds since wrinkled eggs may be a sign of infectious bronchitis (IB). One of the classic symptoms of IB is a lack of spinning in the shell gland, which will cause these wrinkles.

Calcium Deposits

Pimples, bumps, and white or brown spots are common abnormalities in eggs, especially in older hens. These little formations on the outside of the shell are nothing more than deposits of calcium left behind by the shell gland. In young layers, this may be caused by a defective shell gland. If you see a high incidence of calcium deposits, reconsider giving extra calcium if you are.

Soft Or Missing Shells

If you find some weird eggs that appear to have a soft shell, it’s probably a shell-less egg. Sometimes something goes wrong, and the shell gland fails to wrap the egg in a hard shell. The “soft shell” that holds these eggs together is the membrane that is supposed to contain the albumin within the hard outer shell. Sometimes you may find a paper-thin shell, which is more or less the same issue.

Shell-less eggs can be a symptom of a viral disease called egg drop syndrome. They eggs can also indicate a deficiency in available dietary calcium or a lack of other vitamins or minerals in the bird’s nutrition. Stress can also trigger such an event. If you get weird eggs that have no shell on the regular, it’s important you talk to a veterinarian or local extension specialist.

Double Yolks

One of the less weird eggs you may see from your flock is the “double-yolker.” Sometimes, especially in older hens, two yolks are released from the ovary and into the infundibulum at the same time. These two yolks wind up encased inside the same shell and give you a two-for-one deal. These double yolk eggs wouldn’t hatch if incubated, even though that would be cool if they did. There’s nothing special about these eggs otherwise, so go ahead and eat them and don’t worry about seeing them in your egg basket.

Internal Blood Spots

Sometimes you can get some weird eggs that have blood spots in them. Blood in chicken eggs are somewhat common and are usually due to stress in the flock; such as loud noises, other animals chasing them or overcrowding. When formed yolks are dropped into the reproductive tract, they are released by a “sack” that bursts at the ovary. Sometimes a bit of blood from that bursting action stays with the yolk and follows it through to the end.

Meat Spots

Sometimes you may find some eggs that have tissue spots inside them. These small bits of tissue or “meat” spots happen from time to time and happen similarly to blood spots. On occasion, small bits of tissue follow the egg yolk on it’s journey down the reproductive tract and makes for an odd egg. These tissue spots are less than appealing, but feel free to take them out of the albumin when cooking. The eggs are perfectly edible regardless of these spots.

Lash Eggs

Sometimes something goes wrong inside a hen. If a hen releases a yolk and it falls outside the infundibulum, or it hangs up in the tract, it may become a festering infection. Peritonitis, an infection of the abdomen, can ensue, and sometimes these birds deliver an unsightly present in the form of a lash egg. Lash eggs are effectively masses of festering material that passes through the reproductive tract, but it’s not an egg. It may have been a yolk at one point, but now it’s just a mass of infection. It’s usually difficult to identify the culprit in a flock. If you do find out who laid it, seek the opinion of a veterinarian.

Have you seen any of these weird eggs? How often do you get them? Let us know in the comments below!

Originally published in Backyard Poultry and regularly vetted for accuracy.