Aussie Finch Forum

I have had a fawn male St. Helena for some time. Now I also have a yellow hen and a normal cock. I understand that the fawn is sex linked? Am I correct in this? And the normal is dominant. But do not know anything about the genetics of the yellow. Can someone please enlighten me? Thank you in anticipation. Yes I know this is a mix and could prove interesting.
LML

honestly, no clues from me. But I do know you can get yellow - fawn saints. something to try for?

I have enough trouble breeding birds to get too deep into Genetics but I am reasonably sure Fawn Saints are sexed linked.
The reason is I have quite a few in my big flight and each season a couple of chicks turn up that are Fawn and every time they moult out to be male.
This suggests to me that they are sexed linked.

Dunno Passed Biology and genetics doing HSC only 9 years ago and still cant get my head around it all.

Thanks anyway guys and gals. Worst case I will learn from experience. And be able to tell you.
LML

Will take a long time learning by experience . .

This may help . . .

STEP #1 . . YELLOW cock X FAWN hen . . . OFFSPRING: All will be normal in colour (PROVIDED THERE ARE NO HIDDEN "SPLITS" IN THESE PARENTS)but COCKS will be split for both FAWN and YELLOW; Hens will be only split
for yellow and will be of no interest to us

STEP #2 . . DOUBLE SPLIT cock X YELLOW hen . . . OFFSPRING: There are many possible results but among them the ones that are of interest are
YELLOW-FAWN hens (You Beaut!! ) and YELLOW cocks that are SPLIT for FAWN (unfortunately these cannot be distinguished from the yellow cocks that are NOT split for fawn

STEP #3 . . This is a trial and error step if you are using your YELLOW possible split for FAWN cock . . . but mate him with a YELLOW-FAWN hen . . . If any YELLOW-FAWN cocks (You Beaut!! ) appear then you know that he is indeed split for fawn

Obviously you can purchase a YELLOW-FAWN cock to eliminate the trial and error of step 3 . . . but step 3 is the way you would have to go if you were actually producing a brand-new "combination" mutation

PS A key word in all of this is OUTCROSSING . . . incorporating healthy unrelated birds from time to time into your programme

Simple really!?!?! . . . Well not quite so simple as because, since the hoped for offspring will not occur in every nest, periods of good fortune may be few and far between as Mr Murphy applies his laws to those of Br Mendel


PPS The above steps apply when combining any SEX-LINKED mutation with any AUTOSOMAL-RECESSIVE mutation . . . whether the birds be finches, parrots, quails . . . or Strutting Ducks

sure know your stuff!

of course, I didn't understand any of it, but then hey, I'm 12. Something to get onto, then! always useful having a genetecist as mother!!

I know the steps, what I don't know (or didn't till I read your post Arthur) is the genetics of yellows. Didn't have the pleasure of doing any serious genetics at school because I had to go and learn a qualification to go get a job before I was 17. But have managed to pick a fair bit up through reading and trial and error. And the hen is the yellow and the fawn and normals the cocks. Maybe I better e-mail Jarrod and ask if either the yellow or normal are carrying any splits? The fawn should not be. Thanks for your help.
LML

If there are some "hidden" splits in the parents, results will be the same BUT with the addition of that single gene in some of the offspring . . . That is you may get the odd yellow where you have only expected split-yellows . . so hidden splits may well be an advantage in a situation like this

Never too late to learn F/breeder ..I did my HSC when I was 40 years old with 3 kids and a full time job ( and widowed ) . I did it by distance education at my own pace and thoroughly enjoyed it.