Factors?

[matcho]

Can anyone tell me what single and double factors are? I have a YH PB Dilute cock and a RH WB YB cock which both have grey under under their chin. I also have a YH PB Dilute cock and a RH WB Green back which have black under their chins. Now it gets confusing, the White breasted cock with the black chin is a full brother to the yellow back with the grey chin. The Yellow Headed dilute cock with the black chin is a son of the yellow back. So are any of these birds "factors" of some kind and what does it mean to breeding? Any info (in the simplest of terms as I'm no rocket scientist ) would be appreciated.

Matcho

[Diane]

My understanding is that the
single factor = 1 gene
double factor = 2 genes
So a purple chested bird that had a 1 white chested bird as a parent would be for example
BH PC/w GB
or
BH PC single factor white GB
For the white to be visible the bird would need to be double factor for white.
Same thing with the back
Blue isnt visable unless the bird has 2 blue genes (double factor blue)
With the PC yellow DF means the bird is yellow
SF means the bird is inbetween green and yellow as it only has one copy of the yellow gene and therefore the colour is diluted.
With the White chested yellow gouldians the DF and SF can also be easily be determined by the bird having the blue ring around the neck SF or no blue ring DF

[matcho]

Thanks

[Diane]

Do you have the Carlos Matos genetic forecaster? There is a link on here some where along with other forecasters, they have made things so much easier for me to understand

http://www.ladygouldianfinch.com/features_software.mgi" onclick="window.open(this.href);return false;
you can use the above one off line
http://www.amadinagouldove.cz/gouldian- ... e/english/" onclick="window.open(this.href);return false;
this is an online forecaster
I have also a link somewhere to Reverse genetics, will see if I can find that too
Got it...
http://www.gouldiansgalore.net/reverse.html" onclick="window.open(this.href);return false;

[matcho]

Thanks BB

I'll have some fun with those!

[POLAR GOULDIANS]

Hi Matcho,
What you are refering to as a dilute is probably a single factor sex linked yellow. A true Dilute is a recessive colour in the same sense as a Blue backed and Australian Yellow. Anyone outside Australia tends to refer to SF as dilute, because they don't have either the Australian yellow or the Dilute to confuse the issue.
Single factor (SF) or double factor (DF) is becoming the more common way to describe sex linked yellows to avoid confusion with the recessive Australian yellow.
A SF bird has one sex linked yellow gene and one normal green gene , a DF bird has two sex linked yellow genes. The presence of one yellow gene means the bird cannot fully express any black colouring and the black will become a grey colour, two yellow genes removes all black colouring and the black becomes allmost white. A normal bird could be described as DF green, ie : two green genes.
The first two birds you mention will be SF, although the 2nd bird will appear yellow because this happens when you combine SF with white breast. The second two birds will be normals if they both have black under their chins. A cock bird gets one colour gene from each parent, so a SF cock with a normal hen can produce normal sons. I think this is what happened to produce your second YH-PB.
Clear as mud i'm sure.

[matcho]

Polar G's

Have had a look at the birds and sorry there was a mistake. The bird I described YHPB Dilute with black chin is not a dilute but normal green back. Sorry about that. But, the yellow backed, white breast red head, grey chin cock and the red head, white breast, green back cock (which are full brothers) are the product of a YH PB Dilute with grey chin and a RHPBGB hen. Now I am confused! I have no idea what will be the product of this season! Next year will shorten the number of pairs to be a little bit more in touch with the genetics side of things.

[Tiaris]

The terms single factor & double factor only apply in mutations with a dominant mode of inheritence. eg. Yellow-backed Gouldians. Because this mutation is also sex-linked this means you can only get single factor & double factor birds in males. Any yellow backed hens are all single factors.
Fortunately the single factor males look very different to doublefactor ones. Single factor are the lime green pastel/dilute birds where blacks are diluted to slate grey & all other colours remain as per normals.
Doublefactor cocks are clean yellow on the back, blacks are diluted to almost white with a hint of grey & all other colours are as per normal bird.
Any mutation which is not dominant does not have double & single factors at all.