RECESSIVE BREEDING PATTERNS
Next we deal with the Recessive method of inheritance. The Recessive Zebras
that are known to exist in Australia are Whites, Pieds, Grizzles, Black Fronts,
Slates, Yellow Bills,Queensland Isabels and Aluminas.
As with Sex-Linked birds the same method is used to describe a bird that
carries genes for a colour that is not visible in it’s feathering. A Grey cock
carrying hidden genes for White is known as Grey split White, which is written
down as Grey/White. The visible colour is always shown first, and the
hidden colour form second.
The major difference with Recessive mutations is that both cocks and hens
can be split for a recessive colour or a number of recessive colour forms, and
the sex of the parents does not control colour of the young as it does with
Sex-Linked Zebras. Example [1] shows the mating of Grey cock to White hen, but
the same results can be obtained when a White cock is mated to a Grey hen.
Similarly a White cock can be mated to a Grey/White hen to produce the same
expected results as shown in Example [2]. The same rule applies for the other
two Examples given.
The Examples shown on the following pages show what young can be expected when
breeders attempt to breed the White mutation, and if any other colour forms
appear it is obvious that one or both of the parents are split for
another colour. In Examples [3] and [4] where some Grey birds and some
Grey/White birds are bred they are all identical in general overall colour, so
it is impossible to know which are split birds except by future test matings.
NOTE that Grey birds split for another colour almost always appear
identical to pure Grey birds. The illustrations show them as being
different for ease of explanation of their breeding expectations only.
If you wish to breed a Recessive mutation other than White it will be necessary
to substitute the name of that mutation in each place where the word “White”
appears.