Cream Legbar that lays a CREAM colored egg??!?

[NatJ]

Crossing a cream legbar rooster w/brown leghorns gives you easy to sex chicks that lay pale blue eggs. Easy to distinguish and hatch separately

That crossing does not give chicks that can be sexed by their color, any more than purebred Brown Leghorns can be sexed by color.*

Purebred Cream Legbars are color-sexable because males have two barring genes and females have one barring gene. This is because the barring gene is on the Z sex chromosome. Males have sex chromosomes ZZ, so they can have two barring genes. Females have sex chromosomes ZW, so they can only have one barring gene, along with the W chromosome that makes them female.

If you cross a Cream Legbar rooster with a Brown Leghorn hen, every chick inherits one barring gene from the Cream Legbar father. The sons inherit one not-barring gene from the Brown Leghorn mother, so they end up with just one barring gene total. The daughters inherit a W chromosome from the Brown Leghorn mother, and that cannot have a barring gene, so they also have one barring gene.

If you make the cross the other way, with a Cream Legbar hen and a Brown Leghorn rooster, you will get sons with one barring gene (inherited from the Cream Legbar mother) and daughters with no barring gene (because they inherit the W chromosome from the Cream Legbar mother, and that has no barring on it.) The Brown Leghorn rooster does not have any barring genes, so he does not give any to his chicks. The only problem is actually sexing the chicks: they look pretty much alike at hatch anyway (just like how pure Cream Legbar pullets have one barring gene and look very much like pure Brown Leghorn chicks that have no barring gene.)

*Regarding Brown Leghorns, yes the adults can be sexed by color, but by then they have other obvious sex-specific traits too. The young chicks look pretty much alike when they are young. Some people say they can distinguish males vs. females by specific details of the striping pattern, but it is nowhere near as easy as sexing purebred Cream Legbar chicks, which would be why Cream Legbars are considered autosexing and Brown Leghorns are not.

 

[McChooky]

That crossing does not give chicks that can be sexed by their color, any more than purebred Brown Leghorns can be sexed by color.*

Purebred Cream Legbars are color-sexable because males have two barring genes and females have one barring gene. This is because the barring gene is on the Z sex chromosome. Males have sex chromosomes ZZ, so they can have two barring genes. Females have sex chromosomes ZW, so they can only have one barring gene, along with the W chromosome that makes them female.

If you cross a Cream Legbar rooster with a Brown Leghorn hen, every chick inherits one barring gene from the Cream Legbar father. The sons inherit one not-barring gene from the Brown Leghorn mother, so they end up with just one barring gene total. The daughters inherit a W chromosome from the Brown Leghorn mother, and that cannot have a barring gene, so they also have one barring gene.

If you make the cross the other way, with a Cream Legbar hen and a Brown Leghorn rooster, you will get sons with one barring gene (inherited from the Cream Legbar mother) and daughters with no barring gene (because they inherit the W chromosome from the Cream Legbar mother, and that has no barring on it.) The Brown Leghorn rooster does not have any barring genes, so he does not give any to his chicks. The only problem is actually sexing the chicks: they look pretty much alike at hatch anyway (just like how pure Cream Legbar pullets have one barring gene and look very much like pure Brown Leghorn chicks that have no barring gene.)

*Regarding Brown Leghorns, yes the adults can be sexed by color, but by then they have other obvious sex-specific traits too. The young chicks look pretty much alike when they are young. Some people say they can distinguish males vs. females by specific details of the striping pattern, but it is nowhere near as easy as sexing purebred Cream Legbar chicks, which would be why Cream Legbars are considered autosexing and Brown Leghorns are not.

People still can still make mistakes sexing autosexing breeds but a little experience with the line you're breeding it gets easier

 

[McChooky]

That crossing does not give chicks that can be sexed by their color, any more than purebred Brown Leghorns can be sexed by color.*

Purebred Cream Legbars are color-sexable because males have two barring genes and females have one barring gene. This is because the barring gene is on the Z sex chromosome. Males have sex chromosomes ZZ, so they can have two barring genes. Females have sex chromosomes ZW, so they can only have one barring gene, along with the W chromosome that makes them female.

If you cross a Cream Legbar rooster with a Brown Leghorn hen, every chick inherits one barring gene from the Cream Legbar father. The sons inherit one not-barring gene from the Brown Leghorn mother, so they end up with just one barring gene total. The daughters inherit a W chromosome from the Brown Leghorn mother, and that cannot have a barring gene, so they also have one barring gene.

If you make the cross the other way, with a Cream Legbar hen and a Brown Leghorn rooster, you will get sons with one barring gene (inherited from the Cream Legbar mother) and daughters with no barring gene (because they inherit the W chromosome from the Cream Legbar mother, and that has no barring on it.) The Brown Leghorn rooster does not have any barring genes, so he does not give any to his chicks. The only problem is actually sexing the chicks: they look pretty much alike at hatch anyway (just like how pure Cream Legbar pullets have one barring gene and look very much like pure Brown Leghorn chicks that have no barring gene.)

*Regarding Brown Leghorns, yes the adults can be sexed by color, but by then they have other obvious sex-specific traits too. The young chicks look pretty much alike when they are young. Some people say they can distinguish males vs. females by specific details of the striping pattern, but it is nowhere near as easy as sexing purebred Cream Legbar chicks, which would be why Cream Legbars are considered autosexing and Brown Leghorns are not.

Thanks !This cross has a few disadvantages (like sexing the chicks) but the eggs are worth it. I likely wouldn't have considered it but I couldn't find legbars when I ordered chicks last year. I still haven't hatched any chicks from this cross but will be posting pics when I do!

 

[NatJ]

People still can still make mistakes sexing autosexing breeds but a little experience with the line you're breeding it gets easier

I agree. But a little experience lets someone sex Cream Legbars at hatch much more accurately than they would ever be able to sex Buff Orpingtons or White Leghorns at hatch (assuming no vent sexing or feather-sexing hybrids are involved).

 

[Guinea Math]

If you get the whole flock pure for the blue egg gene, with every chicken having two copies of the gene, that is what you will have: all blue eggs and you only need to care about depth of color.

That is definitely the plan!

The crest gene is dominant, so it is possible for a crested chicken to carry the recessive gene for not-crested. If you have birds that are not pure for the blue egg gene, I would keep an eye on other traits as well, just in case.

Ugh. I do have a hen without a crest, I just wasn’t going to use her for breeding (her egg is also a very pale ice blue). But since having that no crested girl, it stands to reason the chances are high that one of the others with a crest is still carrying the recessive gene. Ugh.

 

[McChooky]

I'm not sure how you'd remove these traits out of your flock and build a pure line without replacing any birds but I'm following so I can learn!Thanks!

 

[NatJ]

Ugh. I do have a hen without a crest, I just wasn’t going to use her for breeding (her egg is also a very pale ice blue). But since having that no crested girl, it stands to reason the chances are high that one of the others with a crest is still carrying the recessive gene. Ugh.

You could use the non-crested hen to test roosters. If you hatch a dozen or so chicks from her, and every chick has a crest, then you can safely assume the rooster is pure for the crest gene. Of course you can do this equally well with any other hen that has no crest, no matter what breed she is.

You can use a non-crested rooster to test hens. Again, hatch a dozen or so chicks from each hen, and if they all have crests, you can assume the hen is pure for the crest gene.

In either case, if the Legbar has two blue egg genes, you can sell the chicks as "Easter Eggers." Or if you are doing a cross of blue egg x dark brown egg, you can sell chicks as "Olive Eggers."

But yes, ugh, this adds another layer of difficulty to your project.

If the non-crest hen is otherwise a good example of her breed, you could breed her to a crested rooster, then cross those chicks with crested birds, at which point about half of the next generation will probably be pure for the crest gene-- but you'd need to test mate them to tell which ones are. If it is very hard to get more of the same breed, it might be worth the effort. But if you have some better birds, and a chance of buying more if you want them, then it is much easier to just avoid breeding from the non-crested hen.

 

[McChooky]

So testing requires each rooster to be paired with a blue egg layer and determining whether the chicks breed true for blue eggs and crests when they mature?

 

[NatJ]

So testing requires each rooster to be paired with a blue egg layer and determining whether the chicks breed true for blue eggs and crests when they mature?

Not quite.

You can test for crests while ignoring egg color, and you only have to raise those chicks long enough to see their crests, not to full maturity. But you might choose to work with certain egg colors for other reasons (you sell the chicks and that is what the buyers want, or you keep the females as egg layers and you want certain colors from them.)

You can test for egg color by breeding to a non-blue layer (brown, cream, or white), then raise the daughters to laying age to see if all, some, or none of them lay blue eggs.

Because the blue egg gene is dominant, a hen with one blue egg gene and one not-blue gene will lay blue eggs. So a pullet that inherits the not-blue-egg gene from her mother will lay blue eggs if her father gave a blue egg gene (this proves he has a blue egg gene), or the pullet will lay not-blue eggs if the father gave a not-blue egg gene (this proves that he has a gene for not-blue eggs.)

If you have a hen that lays blue eggs, you do not know if she has one blue egg gene or two blue egg genes. Breeding her to a not-blue-egg rooster is one way to test for that. If any daughters lay not-blue eggs, the hen must have a not-blue gene that she gave them, to go with the not-blue egg gene the rooster gave them.

For these tests, green eggs are also "blue" (the hen has a blue egg gene, but then her egg has brown on the outside so it looks green.)

For the blue egg gene, there is also a genetic test available. Paying for the test will usually be cheaper than doing test matings and raising daughters to laying age. But if you want to raise such daughters anyway, it is cheaper to learn the answer from them instead of also paying for the test.
https://iqbirdtesting.com/blueegg
For that test, you send in a sample of blood or a few plucked feathers, or you can send in the egg a chick hatched out of (the goo inside the shell has enough genetic material for them to test.) Testing the shells from just-hatched chicks will let you know as soon as possible so you can sell or cull the ones that are not what you want, but it only works if you keep track of which chick came from which eggshell.

 

[McChooky]

Not quite.

You can test for crests while ignoring egg color, and you only have to raise those chicks long enough to see their crests, not to full maturity. But you might choose to work with certain egg colors for other reasons (you sell the chicks and that is what the buyers want, or you keep the females as egg layers and you want certain colors from them.)

You can test for egg color by breeding to a non-blue layer (brown, cream, or white), then raise the daughters to laying age to see if all, some, or none of them lay blue eggs.

Because the blue egg gene is dominant, a hen with one blue egg gene and one not-blue gene will lay blue eggs. So a pullet that inherits the not-blue-egg gene from her mother will lay blue eggs if her father gave a blue egg gene (this proves he has a blue egg gene), or the pullet will lay not-blue eggs if the father gave a not-blue egg gene (this proves that he has a gene for not-blue eggs.)

If you have a hen that lays blue eggs, you do not know if she has one blue egg gene or two blue egg genes. Breeding her to a not-blue-egg rooster is one way to test for that. If any daughters lay not-blue eggs, the hen must have a not-blue gene that she gave them, to go with the not-blue egg gene the rooster gave them.

For these tests, green eggs are also "blue" (the hen has a blue egg gene, but then her egg has brown on the outside so it looks green.)

For the blue egg gene, there is also a genetic test available. Paying for the test will usually be cheaper than doing test matings and raising daughters to laying age. But if you want to raise such daughters anyway, it is cheaper to learn the answer from them instead of also paying for the test.
https://iqbirdtesting.com/blueegg
For that test, you send in a sample of blood or a few plucked feathers, or you can send in the egg a chick hatched out of (the goo inside the shell has enough genetic material for them to test.) Testing the shells from just-hatched chicks will let you know as soon as possible so you can sell or cull the ones that are not what you want, but it only works if you keep track of which chick came from which eggshell.

I want to re-home 2 of my last 4 leghorns (keeping the best 2)Still plan on adding some cream legbars but not for 7-8 mo.Thanks for all the info!