Blue egg genetics?

[earthnut]

A punnett square is for one gene. Each animal has two copies of a gene, called alleles, one from each parent. To draw a punnett square, you put the gene pair that one parent has on the top, and the other parent's gene pair on the side. An allele is usually represented by a letter; here I'm using the letter A or a. The dominant allele is capitalized. (in the case of the blue egg gene, the dominant allele would cause blue pigment in the eggshell.) The recessive allele is lowercase. (in the case of the blue egg gene, the recessive allele would simply cause an absence of blue pigment.) Here is a square set up for 2 parents each with one dominant and one recessive allele of a gene:

. parent 1
. | A | a |
. -------------------------
. A | | |
parent 2 ------------------------
. a | | |
. --------------------

Then you treat it like a multiplication table, and each of the bold filled-in squares represents an offspring with two alleles, just like the parents. Each possibility has 1/4, or 25% chance of occurance.

. parent 1
. | A | a |
. -------------------------
. A | A x A | A x a |
parent 2 ------------------------
. a | A x a | a x a |
. --------------------

Also see http://anthro.palomar.edu/mendel/mendel_2.htm for an explanation.

 

[mdbucks]

So If I have an AmerucanaAA and an EE that lays green eggs Aa
parent 1
. | A | a |
. -------------------------
. A | A x A | A x a |
parent 2 ------------------------
. A | A x A | A x a |
. --------------------

So half should lay blue eggs and 1/2 will lay green eggs, so best way to ensure blue or green is to breed a true Amerucana with the EE that lays green already In reality I would get from my dozen eggs(assuming they all hatch) 11 that crow and 1 pullet that refuses to lay so I would never know what genetics got passed on.

 

[Scrambled Egg]

maybe you will get a tye-dyed egg!!

 

[earthnut]

 

[Ole Mule]

The color of eggshells is the result of pigments being deposited during egg formation within the oviduct. The type of pigment depends upon the breed and is genetically determined.

In 1933, Professor Punnett demonstrated that the blue egg factor is a dominant gene (genetic symbol O).

All eggs are initially white, and shell color is the result of the pigments called porphyrins being deposited while the eggs are in the process of formation. In the case of the Rhode Island Red, the brown pigment protoporphyrin, derived from haemoglobin in the blood, is what gives the shell its light brown color.

The Araucana produces a pigment called oocyanin, which is a product of bile formation, and results in blue or bluish-green eggs. Interestingly, the color goes right through the shell, making the eggs difficult to candle during incubation.

This factor is also an indication of the relative purity of the stock in relation to original Araucanas. The original shell color of Araucana eggs is blue, but a variety of colors have been produced by crossing Araucanas with other breeds.

It is known that the color is sex linked - i.e. that the cock is the most important determinant for the color of the eggs in the next generation.

Therefore your cockerel is the most important bird in controlling and improving your egg color in the future.

 

[earthnut]

The blue egg gene is on chromosome 1, not chromosome Z. Therefore it is not sex-linked (chromosomes Z and W are the sex chromosomes in chickens). Other than that, Ole Mule is correct.

"It is known that the color is sex linked - i.e. that the cock is the most important determinant for the color of the eggs in the next generation." is lifted directly off a website on chicken genetics, but they don't give a source for it. All the scientific papers I found talked about it being on chromosome 1.

Locations of a bunch of genes in chickens: http://home.ezweb.com.au/~kazballea/genetics/linkages.html

 

[alohachickens]

I dialed in my friend's incubator that she loaned me yesterday and put the eggs in! Yay!

I included three large olive green eggs of hers, and three nice, bright clear blue ones from my "Easter Egger" Ameracauna hen.

The "Easter Egg" Ameracuana was purchased from Ideal hatchery, and is the most awesome bright, clear, vivid orange color, with blue on her tail. So curious to see what she creates with the Speckled Sussex rooster, if it works. Would they possibly be orange, with the Sussex's black barring and white speckles? That would make them "Candy Corn Chickens!"

Some of the others will be a cross between my black and white speckled Exchequer Leghorns and the Speckled Sussex rooster.

The next batch will have those same Exchequer girls, crossed with a really WILD looking Ameracuana rooster who is mostly light gold, with patches of red and orange on his back/shoulders, and black tipping on his neck feathers and tail.

I'm hoping to get super-colorful chickens from these crosses. I plan on calling my home-made mutts "Aloha Chickens" if it works, (hence my name on here, LOL) because I'm hoping they look like they're wearing bright Hawaiian shirts!

I'll start a new post around day 10 after I candle them and see if it's working . . .

Even if all the blue ones hatch, it will be a while before I see if I get candy corn chickens who lay green eggs, lol. (But, you gotta admit that sounds fun!)

 

[earthnut]

Good luck with your calico chickens! They sound lovely.

If I get into chicken breeding (don't have the space right now), I have this crazy idea of making a blue-egg-laying, blue-feathered, black-skinned, black-boned, blue-eyed, single-combed strain. I just think that would be so crazy and cool - an all-blue chicken!

 

[WoodlandWoman]

With blue ear lobes!

 

[alohachickens]

Earthnut - do chickens sometimes have blue eyes? Or are you just teasing the newbie, LOL! (All I've seen is yellow/orange so far.)