Help me understand the genes!

[nflchickengirl]

2 weeks old
Hatched from BCM egg
(BCM hen x CL roo cross)
Pullet

No crest development yet, not expecting but hopeful.
Coloring seems pretty so far

 

[nflchickengirl]

3 week old
What I thought was pure CL may be mixed??
Her crest is coming in black? Or is that normal? I don’t remember lol.
She hatched from a CL egg.

 

[nflchickengirl]

3 week old marans hen x legbar roo cross.
I’m still team pullet. Her markings are pretty

 

[nflchickengirl]

3 weeks old
Legbar hen x marans roo cross (legbar egg hatch )
Pullet

 

[nflchickengirl]

3 weeks old
Thinking pure CL
Definitely a cockerel

 

[nflchickengirl]

Gangs all here

 

[NatJ]

So I bought a “gamblers dozen” eggs locally that can be the following:

Purebred cream legbar
Cream legbar hen x BCM Roo
BCM hen x cream legbar roo
Pure BCM

Black Copper Marans hen x Cream Legbar rooster should produce chicks that look black, with no chipmunk stripes.

So if a "Marans" egg produced a chick with chipmunk stripes, the hen who laid that egg is not pure for the Black Copper color (specifically, she is not pure for the E^R gene).

based on your eggs

Pure legbar- chipmunk chicks
Legbar rooster X BCM- chipmunk chicks
Pure BCM- black or tuxedo chicks
BCM rooster x Legbar hen- tuxedo or black pullets, and chipmunk cockerels (sex linked!)

I agree about the pure Legbar and the pure BCM.

But if the Black Copper Marans are pure for E^R (Birchen), then they should not produce any chipmunk chicks in a cross with Legbars, since E^R is dominant over e+. That would apply no matter which way the cross is made.

E^R and e+ are not on the sex chromosomes, so even if a BCM rooster x Legbar hen did produce some chipmunk chicks and some black/tuxedo chicks, those color differences would NOT be useful for sexing the chicks. Any of those colors could be on male chicks or female chicks.

Barring is on the Z sex chromosome, so Legbar hen x BCM rooster should give sexlinks with barring: white barring on the sons, but not on the daughters. (The other direction cross would give barring in both sons & daughters, so not sexlinks.)

 

[house1917]

Black Copper Marans hen x Cream Legbar rooster should produce chicks that look black, with no chipmunk stripes.

So if a "Marans" egg produced a chick with chipmunk stripes, the hen who laid that egg is not pure for the Black Copper color (specifically, she is not pure for the E^R gene).


I agree about the pure Legbar and the pure BCM.

But if the Black Copper Marans are pure for E^R (Birchen), then they should not produce any chipmunk chicks in a cross with Legbars, since E^R is dominant over e+. That would apply no matter which way the cross is made.

E^R and e+ are not on the sex chromosomes, so even if a BCM rooster x Legbar hen did produce some chipmunk chicks and some black/tuxedo chicks, those color differences would NOT be useful for sexing the chicks. Any of those colors could be on male chicks or female chicks.

Barring is on the Z sex chromosome, so Legbar hen x BCM rooster should give sexlinks with barring: white barring on the sons, but not on the daughters. (The other direction cross would give barring in both sons & daughters, so not sexlinks.)

@NatJ when you have a sec, would you please elaborate on the Birchen data above. From other Marans threads (and it could be wives tales) there's often concern about introducing Birchens into BCM lines as it can 'mess up' the silver vs. gold coloring of progeny.

Are BCMs a specific kind of Birchen? Or do you bring up Birchen to explain the coloring of the chicks included in the thread.

I was focused on the barring being the key 'tell', and default to the genetics calculator as I'm still reading 'Genetics of Chicken Colours- The Basics'- Sigrid Van Dort's super approachable book!

 

[BastyPutt]

@NatJ when you have a sec, would you please elaborate on the Birchen data above. From other Marans threads (and it could be wives tales) there's often concern about introducing Birchens into BCM lines as it can 'mess up' the silver vs. gold coloring of progeny.

Are BCMs a specific kind of Birchen? Or do you bring up Birchen to explain the coloring of the chicks included in the thread.

I was focused on the barring being the key 'tell', and default to the genetics calculator as I'm still reading 'Genetics of Chicken Colours- The Basics'- Sigrid Van Dort's super approachable book!

 

[NatJ]

@NatJ when you have a sec, would you please elaborate on the Birchen data above. From other Marans threads (and it could be wives tales) there's often concern about introducing Birchens into BCM lines as it can 'mess up' the silver vs. gold coloring of progeny.

Are BCMs a specific kind of Birchen? Or do you bring up Birchen to explain the coloring of the chicks included in the thread.

I was focused on the barring being the key 'tell', and default to the genetics calculator as I'm still reading 'Genetics of Chicken Colours- The Basics'- Sigrid Van Dort's super approachable book!

The confusion comes from "Birchen" being both the name of a gene, and the name of one color variety that has that gene.

The "Birchen" color variety does have the silver gene.
"Brown Red" or "Gold Birchen" or "Black Copper" would be some names of the color variety when it has the gold gene instead of silver.

I was using "Birchen" to refer to the gene E^R, not the other genes involved in the color variety called "Birchen." Yes, I was using it to explain the coloring of the chicks in this thread.

Yes, you are right about the barring.

But chicks with the E^R gene (Birchen) tend to have black down, while chicks with e+ (wild type) have the chipmunk stripes. When you cross the two, you get E^R/e+ and the chicks still look mostly black. They should not have chipmunk stripes. That's the part I was trying to point out.

People breeding Black Copper Marans would not want to introduce Birchen Marans (with the silver gene), just like people breeding Gold Laced Wyandottes would not want to introduce Silver Laced Wyandottes. It's the same basic pattern, but bringing in silver is not helpful when you are trying to get the right shade of gold or copper or red. (It might make sense in some rare cases, but in general it's easier to just keep the colors separate.)