Couples mutations ?

[parrot]

Hi, I would like to know what comes from these couples
male sky blue x female albino
cobalt blue male face yellow x albino female
male green spangle x female green opal
and cobalt male yellow face x mauve yellow face
please help me, thanks

[Hezz]

We haven't a large breeder base, I'm sorry. I'd be asking one of the breeding societies for that sort of information.

[yellowfacedviolet]

There are potentially dozens of possible outcomes for those pairings depending on what the parents are split for (recessive traits) and whether they have some traits in single or double factor.

The only fairly straight-forward outcome is for the last pairing--cobalt x mauve each with yellowface. That will on average produce 50% cobalt and 50% mauve. But even here, what type of yellowface they are (type I, II or goldenface), and whether it is single or double factor, will influence the outcome. As will whatever traits the parents are split for, i.e. opaline, recessive pied etc.

[Hezz]

So much depends on what the parents might be split for, so you would need to know their parentage as well.

[parrot]

Tkanks for your time.

[yellowfacedviolet]

The first two matings involving albino hens will be especially unpredictable since every albino masks color(s) and pattern(s) which will be revealed in (or can be deduced by) the progeny of the matings. If the two cocks are not split for albino, there will be no albinos in the next generation. But if either is split for albino you will have some albino chicks. The second mating, with the yellow-faced cock, raises the possibility of creamino chicks if the cock is split for albino.

[Marianne Marlow]

That's very interesting, I didn't know you knew so much about genetics

[yellowfacedviolet]

Dec 1, 2018 8:52:03 GMT Marianne Marlow said:

That's very interesting, I didn't know you knew so much about genetics

I caught the 'budgie fever' from my mother who raised several generations of budgies over the years. As a  teen, I remember asking her how two of her green birds produced a couple of blues. She answered, "Fred and Ginger are apparently split for blue." She elaborated a bit but I only half understood. That sent me to the library and I read my first book on budgie genetics.

[Marianne Marlow]

Budgie genetics seem very complicated to me!
I can pick out the simpler mutations

Do you have a theory on why budgies have pink, grey or blue feet?

[yellowfacedviolet]

Dec 1, 2018 23:20:59 GMT Marianne Marlow said:

Budgie genetics seem very complicated to me!
I can pick out the simpler mutations

Do you have a theory on why budgies have pink, grey or blue feet?

I only know what I've read about this.  I know fanciers have found this question vexing, wondering why foot color appears to be clearly related to mutation in some cases-- pink feet for recessive pied, ino/albino etc--but not as clearly or consistently related in other mutations.

The most convincing explanation I've read is that color of feet is determined by eumelanin (a form of melanin) which will be influenced by certain factors affecting feather color--albinism, dilution etc-- but absent those influences, can also affect skin independently of color or pattern mutation. And unlike most color/pattern mutations its mode of inheritance is polygenic, meaning multiple genes are involved in the creation of pink, grey or blue feet. This would explain why, for example, two cobalt budgies might each have different foot color.

[Marianne Marlow]

So you think that the foot colour may also be passed down from parents/grandparents as well as be linked to genetic mutation?

It seems complex apart from the albinos, recessive pied, cinnamon, ino's having pink feet that is.

I've had two white double factor spangles, one had pink feet and the one I have now has grey feet. But I think that they had different blue genes in their past, one has small patches of cobalt and the previous (the pink footed one) was sky blue.

[yellowfacedviolet]

Dec 2, 2018 10:21:19 GMT Marianne Marlow said:

So you think that the foot colour may also be passed down from parents/grandparents as well as be linked to genetic mutation?

It seems complex apart from the albinos, recessive pied, cinnamon, ino's having pink feet that is.

I've had two white double factor spangles, one had pink feet and the one I have now has grey feet. But I think that they had different blue genes in their past, one has small patches of cobalt and the previous (the pink footed one) was sky blue.

Yes. A polygenic trait would be greatly influenced by pedigree going back generations.

Albinism (ino/albino) and some forms of dilution (cinnamon, recessive pied etc) affect eumelanin in the skin but when they are not present the multiple genes that control foot color work independently of feather color(s) and pattern(s). I read somewhere that it is akin to the situation in humans where pale-skinned people can have jet black hair. Fanciers became vexed when they realized the linkage between some mutations and foot color and then assumed there must be linkage for the rest of the mutations. 

For breeders, polygenic traits such as this are  exceedingly difficult to breed for or against. The same is true for dog breeders. Fortunately, most of our color and pattern mutations are not polygenic.