Yet another Olive Egger Question....

[BluebirdHomestead]

Can anyone help me understand Olive Eggers created by crossing a Marans with a Silverudd’s Blue (Isbar)? It isn’t as obvious how it works to me since the SBs lay green, not blue, therefore I’m a little confused what genes they pass down. Do they have 2 copies of the blue gene? Will all the F1 crosses lay olive eggs?

Thanks to anyone who can help me out! I’m about to hatch out some Silverudd’s Blues, some SB x Black Copper Marans (Olive eggers), and some Black Olive eggers (Black Ameraucana x Black Copper Marans). I won’t be able to keep all of them so I want to make sure I’m not misrepresenting any of the chicks that I let go.

 

[ChocolateMouse]

Ok, so I know nothing about Silverudds blue isbars. But I know how blue egg genes work and it's like this;

All genes come in pairs. Blue is a simple dominant gene.
Imagine the blue egg gene like a pair of light switches on a blank room.

Each switch is connected to a very strong blue tinted light bulb. The walls are the "default" coloring of the egg without blue. When both switches are off the egg is the default color (white or brown). When you switch one gene on the walls are now tinted blue. When you switch both on the walls are tinted about the same blue but maybe a bit more.
If the walls are normally white, the walls now look blue. If the walls are normally brown they get a bit of a greenish tint. If the walls are dark brown they take on an olive shade.

After that it's punnett squares. Every chicken has two light switches and must pass one down to their offspring at random. If the only switches available to hand down are "off" the eggs will just be default (brown or white).
If a hen lays blue or green eggs we know that they MUST have at least ONE blue switch turned on, because that's how this gene is wired as it were. If they have just one blue egg gene and you breed to a rooster (say, a marans) we know has none the punnett square comes out looking like this;

(Assuming the white is just the aforementioned default egg color here. This would look like two green two brown if the roo was a marans.)

If the hen has TWO blue light switches on they HAVE to give a blue lightswitch to EVERY baby so ALL of the offspring will have one copy of blue from mom and one copy of not blue from dad. They will all be blue egg layers with a 50% chance of passing it down to their own offspring.

(Here's a more sciencey link for you with more detail https://scratchcradle.wordpress.com/2012/07/08/gms2-breeding-for-blue-eggs/)

Now a few things people have scolded me for not mentioning before is that the blue color is actually in the shell of the egg, and the brown color is a coating. But for all intents and purposes the lightswitch metaphor works.
For reference it works on most simple genes. A simple partial dominant gene is like blue-black-splash. The default walls are black, the gene dilutes the black when the lights turn on. With light on the black bird becomes "blue" (ie, grey) and with two lights on they become a very light grey. For a simple recessive gene, the light doesn't turn on unless both switches are on (like a ceiling fan light with both a switch and a pull cord).

Intensity of blueness can be caused by a number of genes, but whether or not it's there at all depends entirely on those two lightswitches.
Brown and brown intensity is controlled by a variety of genes as well. So the best way to get a darker olive is to keep breeding blue egg layers back to chickens with dark brown/olive colored eggs. The eggs being green won't change how olive they come out. White to marans brown is a 100% completely seperate gene.
Many even purebred Ameraucanas carry a little bit of brown in their eggs because a very light brown can actually seem to darken and enhance the blue color of the egg shell. Intensity of brown ranges from a cream colored tint to the extreme dark of a marans egg.

SO! TL DR!
Some SB x Black Copper Marans (Olive eggers), and some Black Olive eggers (Black Ameraucana x Black Copper Marans)

Assuming that your Ameraucanas and Silverudd Blues are both OO (two copies of the blue egg gene on) carriers you will get exclusively chicks that have one gene off (from the marans) and one gene on (from the blue egg layers).

The only way to know for sure that your Blues and Ameraucanas are for sure OO (two switches on) is to breed them a lot to non-blue egg layers, raise the hens, and see if any of them lay brown eggs. If even one chick comes out laying brown eggs, someone is Oo and not OO, because two switches on must ALWAYS hand down a blue egg gene. (This is how you test blue egg roosters too.)

And if your pure silverudd blues come out with any brown egg layers even though they all lay blue they probably have an Oo in there.

Now one would hope all purebred blue egg layers are OO. but it's just not the case. I got some Ameraucanas last year from a registered APA and ameraucana club breeder, and lo and behold one of her chicks lays me BROWN eggs (oo)! That can happen if you breed two blue egg layers together because one combination of Oo and Oo is oo. Which means the rest of the chicks she sent me have a real chance of being Oo too.

So basically it really depends - where'd you get your blue egg layers from and how much do you trust them to be OO?

 

[BluebirdHomestead]

Ok, so I know nothing about Silverudds blue isbars. But I know how blue egg genes work and it's like this;

All genes come in pairs. Blue is a simple dominant gene.
Imagine the blue egg gene like a pair of light switches on a blank room.

Each switch is connected to a very strong blue tinted light bulb. The walls are the "default" coloring of the egg without blue. When both switches are off the egg is the default color (white or brown). When you switch one gene on the walls are now tinted blue. When you switch both on the walls are tinted about the same blue but maybe a bit more.
If the walls are normally white, the walls now look blue. If the walls are normally brown they get a bit of a greenish tint. If the walls are dark brown they take on an olive shade.

After that it's punnett squares. Every chicken has two light switches and must pass one down to their offspring at random. If the only switches available to hand down are "off" the eggs will just be default (blue or white).
If a hen lays blue or green eggs we know that they MUST have at least ONE blue switch turned on, because that's how this gene is wired as it were. If they have just one blue egg gene and you breed to a rooster (say, a marans) we know has none the punnett square comes out looking like this;

(Assuming the white is just the aforementioned default egg color here. This would look like two green two brown if the roo was a marans.)

If the hen has TWO blue light switches on they HAVE to give a blue lightswitch to EVERY baby so ALL of the offspring will have one copy of blue from mom and one copy of not blue from dad. They will all be blue egg layers with a 50% chance of passing it down to their own offspring.

(Here's a more sciencey link for you with more detail https://scratchcradle.wordpress.com/2012/07/08/gms2-breeding-for-blue-eggs/)

Now a few things people have scolded me for not mentioning before is that the blue color is actually in the shell of the egg, and the brown color is a coating. But for all intents and purposes the lightswitch metaphor works.
For reference it works on most simple genes. A simple partial dominant gene is like blue-black-splash. The default walls are black, the gene dilutes the black when the lights turn on. With light on the black bird becomes "blue" (ie, grey) and with two lights on they become a very light grey. For a simple recessive gene, the light doesn't turn on unless both switches are on (like a ceiling fan light with both a switch and a pull cord).

Intensity of blueness can be caused by a number of genes, but whether or not it's there at all depends entirely on those two lightswitches.
Brown and brown intensity is controlled by a variety of genes as well. So the best way to get a darker olive is to keep breeding blue egg layers back to chickens with dark brown/olive colored eggs. The eggs being green won't change how olive they come out. White to marans brown is a 100% completely seperate gene.
Many even purebred Ameraucanas carry a little bit of brown in their eggs because a very light brown can actually seem to darken and enhance the blue color of the egg shell. Intensity of brown ranges from a cream colored tint to the extreme dark of a marans egg.

SO! TL DR!
Some SB x Black Copper Marans (Olive eggers), and some Black Olive eggers (Black Ameraucana x Black Copper Marans)

Assuming that your Ameraucanas and Silverudd Blues are both OO (two copies of the blue egg gene on) carriers you will get exclusively chicks that have one gene off (from the marans) and one gene on (from the blue egg layers).

The only way to know for sure that your Blues and Ameraucanas are for sure OO (two switches on) is to breed them a lot to non-blue egg layers, raise the hens, and see if any of them lay brown eggs. If even one chick comes out laying brown eggs, someone is Oo and not OO, because two switches on must ALWAYS hand down a blue egg gene. (This is how you test blue egg roosters too.)

And if your pure silverudd blues come out with any brown egg layers even though they all lay blue they probably have an Oo in there.

Now one would hope all purebred blue egg layers are OO. but it's just not the case. I got some Ameraucanas last year from a registered APA and ameraucana club breeder, and lo and behold one of her chicks lays me BROWN eggs (oo)! That can happen if you breed two blue egg layers together because one combination of Oo and Oo is oo. Which means the rest of the chicks she sent me have a real chance of being Oo too.

So basically it really depends - where'd you get your blue egg layers from and how much do you trust them to be OO?

Wow this is a wealth of information. Thanks so much for taking the time to lay everything out like that. Here’s where I am unsure - I’m trying to figure out if Silverudd Blue Isbars are OO. They are the only breed to lay green eggs. Not blue or brown. I’m trying to figure out how that plays out when you cross them to something else. Generally a SB bred to another SB lays green. They are supposed to always lay green and an occasional one laying Brown is definitely considered a fault and culled out of breeding programs.
The breeder I’m getting the SB and SB X Marans eggs from is pretty reputable. One of the couple reputable SB breeders in my state and has been working with the breed for 4 years I think.
Super interesting stuff. Thanks for taking the time to reply.

 

[ChocolateMouse]

Wow this is a wealth of information. Thanks so much for taking the time to lay everything out like that. Here’s where I am unsure - I’m trying to figure out if Silverudd Blue Isbars are OO. They are the only breed to lay green eggs. Not blue or brown. I’m trying to figure out how that plays out when you cross them to something else. Generally a SB bred to another SB lays green. They are supposed to always lay green and an occasional one laying Brown is definitely considered a fault and culled out of breeding programs.
The breeder I’m getting the SB and SB X Marans eggs from is pretty reputable. One of the couple reputable SB breeders in my state and has been working with the breed for 4 years I think.
Super interesting stuff. Thanks for taking the time to reply.

Since the blue egg gene does not interact at all with the brown egg genetics this makes sense. The blue goes into the shell itself while the brown is applied with the bloom like a paint - they're totally non interactive parts of the chickens egg production and non interactive genes. A chicken that lays green eggs will always carry at least one blue egg copy (Oo or OO) and have genetically brown egg otherwise.
Brownxbrown will usually be brown. The marans brown is the same genes as the brown of any other brown egg layer, just exaggerated. If you breed whitexbrown or light-brownxmarans-brown, most times the resulting egg color is an inbetween color of what you bred in.

If they've been working for 4 years on their birds one would hope they've test bred out their main stock and culled out any Oo birds, but you can always ask. Not every breeder, even show breeder, knows genetics though so you may have to roll with it and test it yourself.

So in theory or in an ideal world the SBs are OO for blue and a medium-light brown color for brown. So breeding that to a marans would just get you a SLIGHTLY darker olive than breeding, say, an ameraucana (OO, no brown) to a marans. If they're OO, the offspring would still be Oo due to the marans, just a darker olive egg. Maybe more on the brown side than the blue.

But genetics, especially for depth of color, are tricky and you may get some very light greens instead. But chances are good you'll just get an olive color.

 

[Lisa Cleveland]

Since the blue egg gene does not interact at all with the brown egg genetics this makes sense. The blue goes into the shell itself while the brown is applied with the bloom like a paint - they're totally non interactive parts of the chickens egg production and non interactive genes. A chicken that lays green eggs will always carry at least one blue egg copy (Oo or OO) and have genetically brown egg otherwise.
Brownxbrown will usually be brown. The marans brown is the same genes as the brown of any other brown egg layer, just exaggerated. If you breed whitexbrown or light-brownxmarans-brown, most times the resulting egg color is an inbetween color of what you bred in.

If they've been working for 4 years on their birds one would hope they've test bred out their main stock and culled out any Oo birds, but you can always ask. Not every breeder, even show breeder, knows genetics though so you may have to roll with it and test it yourself.

So in theory or in an ideal world the SBs are OO for blue and a medium-light brown color for brown. So breeding that to a marans would just get you a SLIGHTLY darker olive than breeding, say, an ameraucana (OO, no brown) to a marans. If they're OO, the offspring would still be Oo due to the marans, just a darker olive egg. Maybe more on the brown side than the blue.

But genetics, especially for depth of color, are tricky and you may get some very light greens instead. But chances are good you'll just get an olive color.

Can anyone help me understand Olive Eggers created by crossing a Marans with a Silverudd’s Blue (Isbar)? It isn’t as obvious how it works to me since the SBs lay green, not blue, therefore I’m a little confused what genes they pass down. Do they have 2 copies of the blue gene? Will all the F1 crosses lay olive eggs?

Thanks to anyone who can help me out! I’m about to hatch out some Silverudd’s Blues, some SB x Black Copper Marans (Olive eggers), and some Black Olive eggers (Black Ameraucana x Black Copper Marans). I won’t be able to keep all of them so I want to make sure I’m not misrepresenting any of the chicks that I let go.

Out of interest what did your Isbars X Marans produce? Olive or brown? I have the same mix and am curious. Thanks!!