Honestly there are probably tons of combonations that you could try, but let me stress, the best starting point is birds that you've breed yourself so that you KNOW beyond doubt what the genetics of THAT bird are. Next best is birds you get from a breeder who keeps DETAILED and ACCURATE records. If you know what the both parent birds are in phenotype, you can make a pretty accurate guess on what genes your bird has in the DNA.
That said, let's play!
"For example -
I want Red head, Purple breasted, Pastel blue backed chicks. What colour parents do I need to pair up to get those chicks? "
Male = Red Head, Purple Breast, Yellow back and Split for blue
Female = Red or black head, Purple, lilac, or white breast, and Blue back (but having a Green Z gene).
Rember that Pastel blue is only in Male birds with a purple chest, it requires a Green Z and a Yellow Z. Red head is Dom. so you only need a bird with a Red head (preferably one that is Double Factor for red head). Purple breast is Dom so you need just a bird who is double factor for purple chest. You also never want to breed BLUE to BLUE, you always want to breed BLUE with SPLIT for blue!
Or if I want Black head, white breasted, yellow backed chicks - what colour parents should I pair up to get that colour combination in the chicks?
This one's easier
You'll need two black headed white breasted birds, since both black head and white chest are recessive traits.
The back color is going to depend on what your starting with and what your goal is.
For example. I have a cock who is RH, WC, and YB (red head, white chest and yellow back). I also have two dilute cocks (both have one green Z and one yellow Z).
If I breed the dilute cock with a green back female, I have a 1 in 4 chance of getting a yellow backed female bird. This is because Females are ZW and males are ZZ, so only male birds carry two Z chromosomes. Basically there is a 50/50 chance that any one bird is going to be male or female, on top of that there is another 50/50 chance on which Z gene the father passes on to his offspring (will it be green or yellow?)
However, if I breen the Yellow back cock with a green hen, I've now increased my chances to get a yellow back'd bird from the pair to 50/50 (if he's Double Factor for Yellow back, you have to remember that Yellow back males will display the yellow back if they have a lilac or white chest, ONLY purple chested birds will be "Dilute")
OK now my fingers hurt...
I just LOVE gouldian's don't you!!!
