Crossbreed question

[freevillein]

If I have an black Australorp rooster and hens of three different breeds - Delaware, light brahma, white rock - is there any way that the offspring can be completely white? I know that when you cross Australorps with white leghorns the offspring comes out spotted (pretty reliably). I know that you can't completely predict what the offspring will be on some (all?) of these crosses, but I'm just wondering if that one thing - all white - would be possible. The reason I ask this is that I also have a RiR roo in there, and if the Australorp can't produce white offspring with them I can still separate out the sex links at hatching.

 

[Ridgerunner]

That’s a fun one to play with. Let me go through some other stuff first before I get o your actual question.

BA male over Delaware hen – The Delaware hen carries both Silver and Barring, both sex linked genes. With this cross you will get Black Sex linked chicks. Any chicks with the head spot at hatch will be male. The females will not have the head spot. I have not done that cross myself but with the coloring of the chicks’ down I think you will be able to tell the difference.

BA over LB hen – The chicks should all be black, no head spots.

RIR male over Del hen or over the LB hen – You will get Red Sex Links. I haven’t done this exact match but the difference in red chicks and yellow chicks should be really clear.

The White Rock is the great unknown and messed everything up. There are two ways to make a solid white bird, Recessive White paired up over anything or Dominant White over Black, not necessarily paired up with either gene but let’s assume she is pure for both genes at that gene pair for simplicity. There are different ways to make Black too but let’s ignore that for simplicity. White Rocks may or may not have Silver and/or Barring. You just don’t know what is hiding under the White.

Your BA rooster over a WR hen that has Dominant White should give you solid white chicks. Your RIR rooster over this hen should also give you solid white chicks.

Your BA rooster over a WR hen with Recessive White should give you black chicks. If Barring is hiding under the white you could get Black Sex Linked chicks. Sometimes people put barring on solid white chickens to make the white whiter but with hatchery chicks it’s usually not there. Still, it could be.

Your RIR rooster over a WR hen with Recessive white could literally give you anything. If she has Silver you might get Red Sex Links. If she has Barring, especially with black, you could get Black Sex links. If she has mixed genetics hiding under that White you can get a rainbow of chick colors just from her. If her genetics are fairly stabilized under that White, all her chicks may pretty much look the same but I can’t come close to telling you what that would be.

Of course with any of these crosses you can have that spotty leakage, whether it shows up in the down or after they feather out. Most of the time you will not see it in the down but will after they feather out.

Even with the WR hen in the mix, any black chick with the head spot should be a Black Sex Linked male. If you take the WR out of the mix, any red chick should be a Red Sex Linked female. But with the WR hen in there you can’t be sure of anything else. Either rooster could possibly produce a white chick with the WR in the mix.

 

[freevillein]

Wow, this is great; thanks! White rock aren't a sex link bird? Wikipedia, you lied to me!

So if I throw out the white rock (well, move them to another pen), then I'll get:

1. All white chicks are male
2. All brown chicks are female
3. All black chicks could be either

And what was that with the BA x Del? I get that there will be a mark on the head for males, but what will the rest of the coloring be? Some sort of white/black? Stripy chickmonks?

Of course, for any of this to work I actually have to remove my bantams from the coop, because the bantam roosters (Barbu d'Uccle) are big enough to breed my standard hens and REALLY screw up the genetics.

 

[Ridgerunner]

The first post in this thread explains what it takes to make as sex link, regardless of what kind of sex link. There are two basic requirements. The first is that the female has to have the dominant version of the sex linked gene and the male has to have two copies of the recessive version. The other requirement is that you have to be able to see it at hatch. With Red and Black sex links, that means you have to be able to see it in the down.

Tadkerson’s Sex Link Thread
https://www.backyardchickens.com/forum/viewtopic.php?id=261208

Wikipedia did not lie to you. Many hatcheries and some people use White Rocks to make sex links. They know the genetic formula their White Rocks have and it is compatible with making red sex links. Their White Rocks have Recessive White and Silver. They are not based on Extended Black or Birchen. There is no law that says you have to use Recessive White to make a White Rock, you can use Dominant White. There is no law that says a WR has to have Silver, it can have Gold. It can even have black or birchen. Many WR will make red sex links, but not all do.

Your Leghorns are almost certainly Dominant White on Black, remembering there are different ways to make Black. Dominant White on Black is pretty standard for leghorns, that’s a big reason they are usually not used for sex links. But there is nothing stopping a breeder from making a white leghorn using Recessive White. There is nothing in the rules that say a certain breed has to have a certain genetic make-up, it’s up to the breeder to get a color the judge will accept. DNA testing is not required at a chicken show. The judge sees the color the bird has. How the breeder developed that color is up to them.

So if I throw out the white rock (well, move them to another pen), then I'll get:
1. All white chicks are male - yes
2. All brown chicks are female - yes
3. All black chicks could be either

All black chicks could be either except the ones with the white spot on the head are male out of the Delaware. If there is no white spot it could be a female out of the Delaware or either sex out of the LB.

I have not done that Delaware cross with a BA male but I’d expect a chick mostly black with a white front, much like these BA chicks. There are people on here that can tell you that for sure but I’m not one of them.

http://www.feathersite.com/Poultry/CGA/Lorps/BRKLorps.html

 

[freevillein]

oooh, black with a white spot!

This is going to be fun