What egg colors to expect from these couplings

[rbc-bow-chicka]

I have 3 18 week old pullets -- RIR roo × F1 OE hen that will be laying in the next few weeks, hopefully. I kind of *presumed* I would get some flavor of darker OE as a result of that pairing. And now I'm second guessing myself.

I also have 6 18 week old pullets--- EE roo (hatched from green egg) × EE hen (one hen came from green egg, but lays bluer/green. The other hen came from green egg and lays green). I was presuming some kind of green will be forthcoming.

Anyone have a quick and dirty egg color genetic chart or reading material that addresses egg color?

 

[MysteryChicken]

 

[rbc-bow-chicka]

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Oh wow! Thank you !! I had seen the top one before, but not the second one.. and that's the one I think im tangled up in.

Does it really matter if it is a hen or roo.... or just the parentage/egg color that the hen or roo came from?

Like with most things, I'm likely overthinking this.

 

[MysteryChicken]

Oh wow! Thank you !! I had seen the top one before, but not the second one.. and that's the one I think im tangled up in.

Does it really matter if it is a hen or roo.... or just the parentage/egg color that the hen or roo came from?

Like with most things, I'm likely overthinking this.

Order of the breeding doesn't matter as long as one parent carries the blue egg gene.

 

[rbc-bow-chicka]

Thank you for your help!

 

[Ridgerunner]

Like with most things, I'm likely overthinking this.

Overthinking? I can help with that.

Does it really matter if it is a hen or roo.... or just the parentage/egg color that the hen or roo came from?

There is one gene pair that determines the base color of an egg. Each parent contributes equally to that gene pair. Either that gene is base blue or base not-blue. A blue eggshell gene colors the eggshell blue throughout its thickness. A not-blue doesn't color anything, it allows it to default to the base white through its thickness. Blue is dominant over not-blue so if just one of those genes at that gene pair is blue, the eggshell color will be blue. It does not matter of the blue or "white" comes from the father or mother.

If a chicken is "pure" for the blue eggshell gene or not-blue (both genes it has at that gene pair are the same) then it will give its offspring one copy of whatever it has. But if it is split (one of each) then it will randomly pass down one of those genes. It might be the blue, it might be the not-blue. You don't know which it will be.

There are several gene pairs that have been identified as contributing to the eggshell color "brown". Some are dominant, some recessive. Some partially or incompletely dominant. One is sex linked. One is a bleaching gene, it changes a certain brown to white. All of these except one is typically added on top of the eggshell in the last half hour or so that the egg is still in the shell gland after the shell is formed. That "except one" is a tinting gene that gives the egg a slight tint throughout the thickness of the eggshell.

If brown is laid on top of a base white egg, the egg is brown. If brown is laid on top of a base blue egg the egg is green. There are a huge number of potential combinations of all those "brown" genes so you can get anything from a white or blue egg to a dark brown or dark green egg. If you look at a brown or green egg you may see some of the potential of what might be passed down to the next generation but that is just potential. You never know which of those genes will actually be passed down.

I have 3 18 week old pullets -- RIR roo × F1 OE hen that will be laying in the next few weeks, hopefully. I kind of *presumed* I would get some flavor of darker OE as a result of that pairing.

Maybe not. By "F1 OE" I'm assuming this is a first generational cross between a dark brown egg layer breed and a blue egg layer breed. As such she should have one blue eggshell gene and one not-blue. From the RIR rooster his offspring will get a not-blue gene. From the hen about half will get the blue eggshell gene and about half will get a not-blue egg so only half of her pullets will lay a base blue egg.

An OE (olive egger) implies a really dark green egg so dark brown genetics. Most RIR roosters should not have brown genetics that produce a very dark egg, more of a lighter shade of brown. While you never know exactly how those brown genetics will go together, I'd expect most of those green eggs to be lighter than the shell the pullet hatched from if it were very dark.

I also have 6 18 week old pullets--- EE roo (hatched from green egg) × EE hen (one hen came from green egg, but lays bluer/green. The other hen came from green egg and lays green). I was presuming some kind of green will be forthcoming.

A rooster does not lay eggs so you don't know for sure what genetics he has to pass down unless you know a lot about his ancestry. You cannot tell by looking at her egg if the hen has one or two blue eggshell genes. If she is laying a green egg she has at least one green gene. But just because both the mother and father hatched from green eggs does not mean you will automatically get a green egg layer.

If either the mother or father (or both) happen to have two blue eggshell genes then you will always get a green or blue egg layer.

The hen lays a green egg so you know that she has at least one blue eggshell gene. Assume she is split. If the rooster does not have any blue eggshell genes, then half of these offspring will have the blue eggshell gene.

In this case (and to get you something graphic to look at) assume that a upper case "O" stands for the blue eggshell gene and the lower case "o" stands for the not-blue eggshell gene. If the rooster is o,o and the hen is O,o then the chick will get a not-blue from the father (o) and half will get a blue (O) and half get a not-blue (o) from the mother. So half of the chicks will be o,o and half will be O,o. Half of the pullets will lay a base white egg and half a base blue.

If both parents are O,o then about 1/4 of the chicks will get O,O. About half will be O,o. And about 1/4 will be o,o.

Another clarification. I'm mentioning 1/2 or 1/4. These are just the odds for each egg. You have to have enough chicks hatch for these odds to mean anything. Most of our hatches aren't that big.

To me the basics aren't that hard if you have a handle on genetics. The hard part is knowing the genetics of the chickens you are working with. Once you start breeding crosses you don't know what you might get in a specific chicken.

 

[rbc-bow-chicka]

Overthinking? I can help with that.


There is one gene pair that determines the base color of an egg. Each parent contributes equally to that gene pair. Either that gene is base blue or base not-blue. A blue eggshell gene colors the eggshell blue throughout its thickness. A not-blue doesn't color anything, it allows it to default to the base white through its thickness. Blue is dominant over not-blue so if just one of those genes at that gene pair is blue, the eggshell color will be blue. It does not matter of the blue or "white" comes from the father or mother.

If a chicken is "pure" for the blue eggshell gene or not-blue (both genes it has at that gene pair are the same) then it will give its offspring one copy of whatever it has. But if it is split (one of each) then it will randomly pass down one of those genes. It might be the blue, it might be the not-blue. You don't know which it will be.

There are several gene pairs that have been identified as contributing to the eggshell color "brown". Some are dominant, some recessive. Some partially or incompletely dominant. One is sex linked. One is a bleaching gene, it changes a certain brown to white. All of these except one is typically added on top of the eggshell in the last half hour or so that the egg is still in the shell gland after the shell is formed. That "except one" is a tinting gene that gives the egg a slight tint throughout the thickness of the eggshell.

If brown is laid on top of a base white egg, the egg is brown. If brown is laid on top of a base blue egg the egg is green. There are a huge number of potential combinations of all those "brown" genes so you can get anything from a white or blue egg to a dark brown or dark green egg. If you look at a brown or green egg you may see some of the potential of what might be passed down to the next generation but that is just potential. You never know which of those genes will actually be passed down.


Maybe not. By "F1 OE" I'm assuming this is a first generational cross between a dark brown egg layer breed and a blue egg layer breed. As such she should have one blue eggshell gene and one not-blue. From the RIR rooster his offspring will get a not-blue gene. From the hen about half will get the blue eggshell gene and about half will get a not-blue egg so only half of her pullets will lay a base blue egg.

An OE (olive egger) implies a really dark green egg so dark brown genetics. Most RIR roosters should not have brown genetics that produce a very dark egg, more of a lighter shade of brown. While you never know exactly how those brown genetics will go together, I'd expect most of those green eggs to be lighter than the shell the pullet hatched from if it were very dark.


A rooster does not lay eggs so you don't know for sure what genetics he has to pass down unless you know a lot about his ancestry. You cannot tell by looking at her egg if the hen has one or two blue eggshell genes. If she is laying a green egg she has at least one green gene. But just because both the mother and father hatched from green eggs does not mean you will automatically get a green egg layer.

If either the mother or father (or both) happen to have two blue eggshell genes then you will always get a green or blue egg layer.

The hen lays a green egg so you know that she has at least one blue eggshell gene. Assume she is split. If the rooster does not have any blue eggshell genes, then half of these offspring will have the blue eggshell gene.

In this case (and to get you something graphic to look at) assume that a upper case "O" stands for the blue eggshell gene and the lower case "o" stands for the not-blue eggshell gene. If the rooster is o,o and the hen is O,o then the chick will get a not-blue from the father (o) and half will get a blue (O) and half get a not-blue from the mother. So half of the chicks will be o,o and half will be O,o. Half of the pullets will lay a base white egg and half a base blue.

If both parents are O,o then about 1/4 of the chicks will get O,O. About half will be O,o. And about 1/4 will be o,o.

Another clarification. I'm mentioning 1/2 or 1/4. These are just the odds for each egg. You have to have enough chicks hatch for these odds to mean anything. Most of our hatches aren't that big.

To me the basics aren't that hard if you have a handle on genetics. The hard part is knowing the genetics of the chickens you are working with. Once you start breeding crosses you don't know what you might get in a specific chicken.

I have read this several times..... more than several i guess.... and I wanted to express how thankful I am that you took the time to explain all of this in terms I could understand.

I have a sketchy grasp on genetics and find this so incredibly fascinating.

I will probably keep referring back to it, honestly!!!