Here is a site, also available in application, dedicated to the calculation of the genetics of zebrafinch. ZebraCalc allows you to have the probabilities of results depending on the mutations of the respective parents.
Before that, we will obviously need to know the genotype of each parent. To help you determine the mutation or combination of mutations to which your zebrafinch belong, you can refer to: Illustrated glossary of mutations in zebrafinch.
That said, I would say that this application is only an aid. The best thing will always be to understand how each mutation is transmitted. For this, I also advise you to have a good basis to consult the article: Zebrafinch genetics : Instructions.
The objective of this article is not to impose a management of breeding or create a controversy, but to share my experience of breeding, my observations as well as the difficulties I have encountered for about fifteen years of breeding zebrafinch in this combination of mutations.
The black breast is a mutation of design due to a different distribution of eumelanim in the plumage of the bird. The orange breast mutation is a color mutation: The eumelanin of the designs is transformed into brown orange phaeomelanin, which pulls towards the red-rust color for the best subjects. I do not think it is important to specify in detail how each mutation we already know alters on the mutated bird.
The ideal competition male, in addition to a correct shape and size such as a classic, must have no black discharge into the chest, must have a parotic zone (the color: between the beak and the cheek) white, a chest that rises as high as possible under the beak, a strong extension of the cheeks (the cheeks meet at the back of the skull) without running on the back (which for me represents a non-selective extension of the color), a gray back and not loaded with brown veil as is often the case, drawings on primary and secondary remiges (white+orange), the most intense red/rust color possible, the largest belly design (orange flames). To this it is necessary to add that the drawings of blanks must be marked with white ovals on orange background; The drawings of the tiles of tails are of course elongated.
The female as the male must be gray of back, shape and size correct, have a belly drawing (the flames)( note that this drawing is not orange as on the males but rather pulls towards the gray-brown), back drawings (on the outer edge of the remiges), a chest that rises very high, drawings of orange cheeks, flanks marked with dots and orange color also.
Should the female have the darkest possible cheeks and flanks ? I have no answer.
What is certain is that the first female orange breast had no orange cheeks and that the Dutch standard required females without cheeks a few years ago (now there are two standards accepted and judged differently: with drawing and without drawing…: type 1, type 2 in competitions). The female without drawn cheeks keeps the tail tiles as orange as possible. Most of my breeding females do not have cheeks, it is a character that I do not select specially.
I sometimes read on the internet that to release a good intensive male in color it is absolutely necessary a female with very orange cheeks, it is not true. We come out very good colored birds with females without cheeks if they are very grey. By “very grey” I mean birds whose eumelanin supersedes phaeo. This does not mean that certain characters should not be present (belly drawing, caudal overlying, eyelid etc.). I can say that the female without cheek has no influence on the intensity of the color on the males.
Some peculiarities are specific to the mutation combination
The orange breast seems to intensify the extension of the orange color of the drawings. We often observe subjects with a complete extension of the cheeks at the back of the skull, and this with a chest that goes up very high under the beak (compared with a pure black chest). This extension, when important, tends to color the color. I do not agree with those who say that orange-colored birds are black-faced birds. This coloration appears as well on black breast orange breast without the black face mutation for several generations.
I do not select the orange color of the color. Certainly it is a defect present in my birds but raising black face black breast orange breast, I do not pay attention to it.
In competitions, it depends a lot on the judges but in general, if the bird is good, they do not get heavily punished. Note that there are several kinds of orange colors, which a photo does not show well. Rusty orange colors like the chest and that come to blend with the cheek (not good) or an orange veil, lighter than the cheek and that stands out again (it goes better). But on big competitions, this is what the beautiful bird will miss to rank against the best.
I made this glossary to illustrate in photos the existing mutations in the zebrafinch.
He can help you identify the mutation (s) of your zebra finches.
Important precision :To identify the genotype of your zebrafinch, it will be necessary to take into account that a zebra finch can carry a mutation without being mutant.
Being a carrier (/, split) of a mutation means that it is partially present (genetically speaking). From the visual point of view the partially carried mutation will not be seen or only by some clues present in the appearance of the bird.
In this case, it will be necessary to have a trained eye to determine the genotype. Sometimes check couplings will be necessary.
Your zebra finch can also have several mutations, the possible combinations are numerous.
This glossary is based solely on the phenotype (visual characteristics) and single mutations (not combined).
The gray zebrafinch is not a mutation, it is the original (wild) type.
1. Gender-related mutations
The female can never be a split, so she is either mutant or non-mutant.
The male can be a split of the mutation.