Basic Zebra Finch Genetics...Although knowledge of the inheritance of colours in Zebra Finches is not essential to be a successful breeder and exhibitor, a basic knowledge of the subject can be of assistance. Sometimes colours are bred unexpectedly and usually the reasons for these cropping up can be determined from a few basic matings. Equally we do not always have exactly the right birds at the start of each breeding season, with a little basic knowledge of genetics we can often work out the best way to pair together birds of different colours, in order to produce youngsters to be used usefully in future years.
Genetically pure birds are those which only produce genes for their own visual colour, split birds produce genes for their visual colour and also genes for the other colour forms which are masked within their genetic make up. When a bird is pure i.e. a pure Normal, it is written as Normal, when a bird is split i/e Normal split for Pied, it is written as Normal/Pied. For the purposes of this list of matings, colours can be regarded as either Recessive, Dominant or Sex Linked, these terms referring to their relationship to the Normal colour form.
Pieds, Whites, Penguins, Recessive Dilutes and Yellow Beaks are recessive Colours.
Dominant Dilutes i.e. Silvers and Creams are Dominant Colours.
Fawns, Lightbacks and Chestnut Flanked Whites are Sex Linked Colours.
Normal X Recessive Colours (e.g. Pied, Which can be substituted by any other recessive colour)
Normal. x Pied. = 100% Normal/Pied..
Normal/Pied. x Pied. = 50% Normal/Pied + 50% Pied..
Normal/Pied. x Normal/Pied. = 25% Normal, 50% Normal/Pied + 25% Pied..
Normal/Pied. x Normal. = 50% Normal + 50% Normal/Pied..
Pied. x Pied. = 100% Pied..
Normal x Dominant Silver (Dominant Silvers can be double factors (d.f.) or single factors (s.f.) Regard (d.f.) Silvers as pure Silvers and (s.f.) as silver/Normal).
Normal. x (d.f.) Silver. = 100% (s.f.) Silvers..
Normal. x (s.f.) Silver. = 50% Normal, 50% (s.f.) Silver..
(s.f.) Silver. x (s.f.) Silver. = 25% Normal, 50% (s.f.) Silver +25% (d.f.) Silver..
(d.f.) Silver. x (s.f.) Silver. = 50% (s.f.) Silver +50% (d.f.) Silver..
(d.f.) Silver. x (d.f.) Silver. = 100% (d.f.) Silver..
Double factor Dominant Dilutes are quite rare, the vast majority of Dominant Dilutes are single factor birds.
Normal x Sex Linked (e.g. Fawn which can be substituted by any other sex linked colour).
Normal Cock. x Fawn Hen. = 50% Normal/Fawn Cocks + 50% Normal Hens..
Normal/Fawn Cock. x Fawn Hen. = 25% Normal/Fawn cocks,25% Fawn Cocks,25% Fawn Hens +25% Normal Hens..
Normal/ Fawn Cock. x Normal Hen = 25% Normal/Fawn Cocks 50% Normal Cocks & Hens + 25% Fawn Hens..
Fawn Cock. x Normal Hen. = 50% Normal/Fawn Cocks + 50% Fawn Hens..
Fawn Cock. x Fawn Hen. = 100% Fawns Cocks & Hens..
With Sex Linked Colours, the sex of the parent birds used is very important in determining the colours which will be produced. Only cock birds can be split for Sex Linked Colours, visual hens never being split for Fawn, C.F.W. or Light Back.
From these basic matings we can see that when two Normals are paired together, if they are carrying genes for the appropriate colours, they can produce any of the Recessive Colours and Hens of any of the Sex Linked Colours. Birds can carry more than one colour hidden in their genetic make up and therefore in theory it would be possible for Whites, Penguins, Pieds, Recessive Dilutes, Yellow-Beaks, Fawn Hens, C.F.W. Hens and Light Back Hens to be produced from just one pair of Normals.
When we pair two different colours together the young produced will often revert back to Normal .e.g. Pure Penguin paired to a pure White will only produce visual Normals, these birds being split for both Penguin and White. In present day exhibition stock the vast majority of Whites are in fact White Pieds, and as many visual Pieds are split for White, when Pieds and Whites are mated together Whites and Pieds are produced rather than Normals.
White. x Pied. = 100% Normal/Pied & White..
Normal/Pied & White. x White. = 25% Normal/Pied, 25% Normal/Pied & White, 25%Pied + 25% Pied/White..
Normal/Pied & White. x White. = 25% Normal/White, 25% Normal/Pied & White, 25% White +25%White/Pied..
Pied/White. x Pied/White. = 25% Pied, 50% Pied/White +25% White Pied..
White/Pied. x White/Pied. = 25% White, 50% Pied/White + 25%White Pied..
Pied/White. x Pied/White. = 50% Pied/White + 50% White Pied..
With Sex Linked Colours it is slightly different, and as there is a very close relationship between C.F.W's and Light Backs combining these two colours produces unusual results. The cause of this anomaly is that the C.F.W. and the Light Back genes occur in exactly the same position on the X chromosome.
Fawn Cock. x C.F.W. Hen. = 50% Normal/Fawn & C.F.W. Cocks + 50% Fawn Hens..
C.F.W. Cock. x Fawn Hen. = 50% Normal/Fawn & C.F.W. Cocks + 50% C.F.W.Hens..
Normal/Fawn & C.F.W. Cocks can produce both Fawn and C.F.W's when mated to Normal Hens..
Light Back Cock. x C.F.W. Hen. = Light Back/C.F.W. Cocks + Light Back Hens..
C.F.W. Cock. x Light Back Hen. = Light Back/C.F.W. Cocks + C.F.W. Hens..
Light Back/C.F.W. Cock. x C.F.W. Hen. = Light Back/C.F.W. Cocks + C.F.W. Hens..
Light Back/C.F.W. Cock. x Light Back Hen. = Light Back Cocks, Light Back/C.F.W. Cocks, Light Back Hens, + C.F.W. Hens..
By mating Sex Linked Colours to Recessive Colours we can produce birds which are split for colours combining the colour characteristics, such as Fawn Pied and C.F.W. Penguin, by pairing these birds back to the appropriate Recessive Mutation, visual Fawn Pieds, Fawn Penguins, C.F.W. Penguins, Light Back Yellow- Beaks, etc. can be produced.
The Dominant Dilute Mutation can also be combined with both Sex Linked and Recessive Colours, when combined with Fawn it produces Creams and multiple combinations such as Dominant Cream Penguin Pieds could be produced if desired.
Always remember the percentages of colours produced can vary greatly from nest to nest, and will only correspond to theory if several hundred birds were bred from one pair. If you would like to study colour inheritance in greater detail the Z.F.S. Mating list is a very useful guide to colour expectations, this book can be purchased through the Zebra Finch Society General Secretary, details of how to order this publication can be found in the section on Merchandise (see main heading on front page of this website) or in the Zebra Finch Society magazine on Publications.