Yellow gouldians - YB vs Aus vs??

[natamambo]

I'm fine with the genetics of the YB and the Aus Yellow. I understand the dilution factor of the "YB" in the blue creates silver. Happy to accept that an Aus yellow always has a white bib as the melanin is absent (but I do wonder if that is the case why it frequently seems to be paired with WB normals to create the splits, this last bit seems unnecessary). But what happens if a bird is both YB and Aus Yellow? Logically such a bird is possible because the YB gene (which really should be called a dilution gene except that there is also a recessive dilute just to confuse the issue) can be present on any bird.

The reason for my question is in part inspired by a bird I picked up on Friday from a dealer (actually went to sell red rumps not buy gouldians but this guy was too good to resist). From all the photos I've seen of Aus yellows, the only thing holding me back from believing he is Aus Yellow is the purple bib, which is present but duller than the other cocks and is almost as dull as the brightest hen I have. The face is a bright red not a dark red like the rest, almost fire engine red.

In my set of YB birds, accumulated over the past fortnight from different sources I now have:
* a YBDF BH cock (except of course the face is white) whose bib is almost blue rather than purple and who has a very slight green tinge in the yellow on the back
* a YBDF RH cock whose bib is normal bright purple and who has a very slight green tinge in the yellow on the back
* a YBDF RH hen whose bib is normal light purple and who has a very slight green tinge in the yellow on the back
* the new guy, who has no green in him at all, he is brighter yellow than most canaries on his back but light yellow, almost white, on the wing tips and even brighter on his belly. Is this much variation in the amount of yellow normal or is there something else at play in this bird?

The BFYB cock showing the blue bib:


The RFYB cock note bib colour of BFYB behind him:


The RFYB cock showing back:

[Diane]

That bib is certainly tending more to blue.
I could be typing complete rubbish here, but here goes......could the blue bib be caused by a lack or reduction of red pigment?
You certainly have got a variety of unusual gouldians there, at least you will be able to understand how the genes work in the young!

[Matt]

I am only viewing the pics on my phone but his breast colour does look a little light for purple breast. Could he be lilac? Lilac has the same effect on yellow backs as white does.

[Matt]

The purpose of mating an aus yellow bird to a white breasted normal is to ensure a clean white breast. Many gentically purple breasted aus yellows will carry a patch or two of purple still on their breast. If you want the cleanest yellow bird possible, combine the white breast, aus yellow and euro yellow.

[cranberry]

The purpose of mating an aus yellow bird to a white breasted normal is to ensure a clean white breast. Many gentically purple breasted aus yellows will carry a patch or two of purple still on their breast. If you want the cleanest yellow bird possible, combine the white breast, aus yellow and euro yellow.

OK back it up a little. Muchos confuso!

Please correct me if I'm wrong but I am led to believe the Aus Yellows cannot be purple breasted...even slightly. Their genetics dictate they cannot carry any dark pigment on their breast. The only purple breasted yellow bird is the Euro yellow. An Aus Yellow may also be carrying the white breasted gene but it will not enhance their already white breast which is given to them through the Aus Yellow gene. It is incorrect to say an Aus Yellow is white breasted because by definition, an Aus Yellow has a white breast without needing to carry the white breast gene. White Breast and Aus Yellow are 2 separate mutations.

But then again, what would I know???

I have a supposed Aus Yellow that still has a light blue ring around his head. This leads me to believe that he may be a Euro Yellow and not Aus Yellow. I will attempt to do some test matings with him to a normal hen this year to see what I get.

[cranberry]

And here are some pics of the said Aus Yellow (perhaps Euro Yellow)...

Gouldian 001 (Small).jpg

Gouldian 002 (Small).jpg

Gouldian 003 (Small).jpg

Gouldian 004 (Small).jpg

Gouldian 005 (Small).jpg

[natamambo]

Cranberry my understanding of the genetics is the same as yours, that Aus Yellow totally lack melanin and therefore can never have any purple. This is supported by Don Crawford http://www.gouldianfinch.com.au/austral ... _finch.htm. It seems we have birds of interest for different reasons.

The reason why I find my two interesting and got them was:
* The blue bib on the BF (which incidentally has no black grey or blue pencil line at all, his face is white and then the bib starts), while striking, as a geneticist it was clearly different too
* The bright yellow and muted bib of the latest, I suppose lilac is possible but if so it's deeper than any other lilac I have seen. While a RF he too (as do all my other YB) totally lacks the pencil line.

In all cases the absence of the pencil line is in clear contrast to your own bird. My own theory on your bird is that is a YBSF but the white bib is brightening the yellow (by eye at least if nothing else). You need to deliberately cross breed him with two different hens this season, one being a normal and the other being a YB. If he is Aus yellow at least you'll have a good range of splits to choose from (they'll all be splits and all hens will be normals and all cocks SFYB). You'll be able to tell if he's SF or DF YB by the pairing with the normal as any normal cocks means he can't be DF.

[Matt]

Cranberry, I believe your bird is a euro yellow.

The retention of melanin in the Australian yellow mutation is why you see the green foul feathering on the back. This melanin retention can be great enough to show some purple on the breast or some black on a black headed bird. The white breast mutation can be used to mask any melanin retention on the breast. The euro yellow can be used in the same way to hide the foul feathering on the back.

[cranberry]

Looks like some test matings are in order this year. I hope the boys are up to it!

So I possibly have DF Euro Yellow White Breast cocks or Aussie Yellow cocks. Time will tell!

[finchbreeder]

Love that blue breast. But the genetics of these guys is outside my range of study/understanding.
LML