Head colour genetics

[iaos]

Hi folks,

Is it possible to get YTB out of a pair of BH RTB?

I have only noticed this morning that at least 3 of my young birds are YTB. I have never noticed it in my flock before, maybe I need my eyes checked... Haha.

What is the mode of inheritance for YTB?

Cheers Ian

[KENTUCKY]

The correct answer is yes, because both parents are Type b BHs, indicating that both parents carrying one gene for YH,
what you have bred are in fact Type c BHs and are also hidden YHs, there is a Poster available on our forum that explains the Head Colour Inheritance of the Gouldian Finch
in detail, great Christmas Present.
PM me for more info if interested.

[KENTUCKY]

Add on to my previous Post
Mode of Inheritance is Autosomal Recessive

[iaos]

Thanks Kentucky. Glad this is the case and I haven't been missing a YTB in my flock.

Looks like I have at least 2 cocks and a hen YTB out of the pair.

Cheers Ian

[E Orix]

Ian
I have a good strain of pure Black Headed Gouldians and frequently they turn up with Yellow Tipped beaks.
I accept that but not having any interest in Gouldian genetics I often ask why doesn't a yellow headed turn up
I have enough trouble breeding birds let alone try and grasp genetics.

[KENTUCKY]

YHs cant make an appearance because BHs can only produce BHs being a sex linked recessive.
for YHs to crop up you would have to pair up a YTB either to a Yellow head, or a Red split to yellow head, ( Cock or Hen) or a Red/yellow head/black head,( Cock only) no such Hens exist.
I particularly like the YTB BHs, observed in early morning sunlight is a sight for sore eyes,a bright Yellow Tip, followed by the black of the head and combined with the sky blue head band is stunning, nature at its best but, then again I am bias.

[BrettB]

This is an interesting phenomenon, so I would like to explain the the same thing, but in a different way.

The gene for yellow head is autosomal recessive. Birds with a single gene show no outward characteristics.
Birds with two yellow head genes (homozygous) will express yellow in the place of red.
In the case of black heads, only the tip of the beak will express the yellow.
If the bird would have been a red head, then it will express as a yellow head .

When I was setting up a pure strain of Black heads, I tried to think of a way to prevent this, but in the end it was just too hard.
I just accept that occasionally this "natural" mutation will pop up.

Cheers
Brett

[Tiaris]

Another way of looking at it is YTB BHs are actually Black-headed & Yellow-headed in the same bird. The black masks the yellow so only the yellow bill remains to be seen.
Any RTB BH parent of a YTB BH is split to YH.

[E Orix]

It's all good and now I can relax and watch my normal Black Headed Yellow Beaked Gouldians.

[KENTUCKY]

The YTB Gouldian is the only Gouldian that will display his/her genetic make up by his/her outside appearance
all others are more secretive and need to produce youngsters to determine the genetic make up of the parent birds.