Silkie chickens are known for their unique appearance and fluffy plumage that resembles silk or fur. But another distinctive feature of Silkies is the color of their eggs. While most chicken eggs are brown or white, Silkie eggs can come in shades of blue, green, or cream. So what determines the color of Silkie eggs and why are they different than other chicken eggs? Let’s take a closer look.
What Causes Blue Eggs?
All chicken eggs start out white inside the hen’s body. Pigment is added to the egg shell as it passes through the oviduct, with brown eggs getting their color from a pigment called protoporphyrin. For blue or green egg layers like Silkies, a different pigment called oocyanin is deposited on the eggshell as it forms.
Oocyanin is a biliverdin pigment that comes from the breakdown of red blood cells. As the developing egg travels through the oviduct, oocyanin is secreted onto the eggshell by the cells lining the oviduct. The more oocyanin that is deposited, the deeper blue-green the egg color will be.
Some breeds of chickens have the genetic capability to produce oocyanin pigment while others do not. Silkie chickens have this genetic coding for blue eggs, which is why their eggs can range from deep aqua to light blue-green in color.
How Dark Are Silkie Eggs?
The exact shade of a Silkie egg can vary from hen to hen. Some Silkies lay eggs that are a very deep robin’s egg blue, while others produce lighter turquoise eggs. The intensity of color comes down to genetics as well as individual variations between hens.
Younger Silkie hens often lay eggs with lighter colored shells at first. As the hen matures and continues laying, her eggs usually become a darker blue. The age and health of the hen can also affect shell color.
|Silkie Hen||Egg Color|
|Hen 1||Pale Blue|
|Hen 2||Robin’s Egg Blue|
|Hen 3||Deep Aqua|
As shown in the table, Silkie hens can produce eggs ranging from a light pastel blue to a very bold deep blue. But no matter what the shade, the blue egg color is what makes Silkies stand out from other backyard chickens.
Do All Silkies Lay Blue Eggs?
While blue or green eggs are characteristic of the Silkie breed, not every individual hen will lay colored eggs. There are a few reasons why a Silkie may produce white or cream eggs instead:
- Genetic variations – Some Silkies carry genes for white eggs rather than blue.
- Mixed breed ancestry – Silkies with mixed background can default to laying white eggs.
- Age of hen – Young Silkies often don’t start laying blue eggs until maturity.
- Stress factors – Molting, illness, or nutritional deficits can affect egg color.
Even purebred Silkies that come from lines selected for egg color can occasionally produce white eggs. Don’t be surprised if one hen in your flock lays eggs that are a different shade than the others. Individual variations are normal.
Are Colored Eggs Nutritionally Different?
When it comes to nutritional content, colored eggs like those from Silkies have the same quality as white eggs. The only difference is the pigment deposited on the shell. The nutrients within the egg itself are the same regardless of shell color.
Testing has shown no significant differences between blue, green, brown, or white eggs when comparing factors like protein content, cholesterol levels, vitamins, and mineral content. Shell color does not change the egg’s interior quality.
How the Blue Egg Color Is Produced
Let’s take a closer look at how oocyanin pigment leads to blue-shelled eggs as an egg develops inside a Silkie hen:
- Yolk and white form in the ovary, surrounded by a clear membrane.
- As yolk travels down the oviduct, the egg shell starts forming.
- Oocyanin is secreted by the cells lining the lower oviduct.
- Oocyanin is deposited onto the developing shell, coloring it blue-green.
- A thin outer layer called the bloom seals the pigment in the shell.
This explains why only the outer shell becomes blue, while the inside contents remain white and yellow. The pigment never penetrates through the shell membrane into the interior of the egg.
Are Blue Eggs Safe To Eat?
Since the blue or green color is simply pigment on the eggshell, blue eggs from Silkies and other breeds that lay colored eggs are just as safe to eat as brown or white eggs. The color has no effect on flavor, quality, or nutritional density.
Blue chicken eggs are completely edible and can be enjoyed cooked any way you would normally prepare white or brown eggs. Scrambled, fried, poached, or baked, their rich color provides visual appeal in addition to great taste and nutrition.
Reasons Silkies Lay Colored Eggs
So what are the key reasons behind Silkies and other breeds laying blue or green eggs?
- Genetics – Silkies have the genetic coding to produce oocyanin pigment.
- Oocyanin deposits color as eggshell forms in oviduct.
- Color intensity depends on amount of pigment deposited.
- Individual hens vary in exact egg shade.
In the end, it comes down to the unique genetics of Silkie chickens that allow them to manufacture and deposit colorful oocyanin pigment onto their eggshells as the eggs develop. This intriguing trait is part of what makes Silkies special!
Other Chicken Breeds That Lay Colored Eggs
Silkies are the most well known blue egg layers, but there are some other breeds of chickens that can produce colored eggs too. These include:
- Ameraucanas – Shades of blue or green
- Araucanas – Blue or green eggs
- Easter Eggers – Blue, green, pinkish or brown eggs
- Olive Eggers – Olive green eggs
- Marans – Chocolate brown eggs
So Silkies aren’t the only chickens that lay green and blue eggs. But their fluffy feathers and broody mothering instincts make them one of the most endearing of the blue egg laying breeds.
To recap the key points:
- Silkie eggs can range from pale blue to deep aqua in color.
- The blue color comes from oocyanin pigment deposited on the shell.
- Not all Silkies will lay blue eggs due to genetic variations.
- The interior quality of colored eggs is the same as white eggs.
- Ameraucanas, Araucanas, and Easter Eggers also lay blue or green eggs.
So while Silkie egg color is unique, it does not affect the egg’s safety or nutritional profile – blue shells simply provide a fun splash of color in the chicken coop! Their distinctive blue eggs are just one more thing that makes Silkies such special chickens.