What is covered by
Dominant White in Pigeons
Dominant white, an early
described but long overlooked hereditary factor
In 1925 Joseph R. Walker had
presented his analysis of white colouration, and among them Dominant
White. In homozygosity, white or almost white colouring is caused by
the factor. Heterozygous are largely white, but also have coloured
feathers to an appreciable extent. The variation in F1
may be seen in the fact that the factor covers other factors present
in the genome in different ways (Sell, 2012, 2015). A Dominant White
(Wh) that genetically has a black or heterozygous black/dominant red
base colour will inherit differently than Dominant White based on
pure Dominant Red.
Stralsund of the flying type (dominant white) x blue check homing
hen with two differently coloured youngsters. The black-grizzle
youngster shows that the male is at least heterozygous for both
black pigment and the colour spread factor. Next to it a tail-marked
juvenile from white parents with 'flash-grizzle'-like brightenings
in the tail, pearl-eyed like the parents.
The factors hidden under the
epistatic (covering) white can be revealed by mating back to solid
colours and in an F2. Most of the tested whites in the
own loft had a dominant red base colour, some had a black one. Often
the colour spread factor is revealed in crosses. Besides this also a
dominant grizzle factor, identical or similar to grizzle (G). Walker
(p. 598) also received coloured kittens from a mating of F1
among themselves. From his crossings, he concluded that there was a
mendelian factor that was independent of the other white factors.
After crosses, and from pure white pairs, not just one time, magpies
and tail-marked whites are raised. They resemble flash grizzle in
the tail. Platinum was also discovered after crosses among the white
Pomeranian Eye-Crested Highflyers, anchored in the breed decades ago
(Sell, 2012, pp. 169ff., 476f.) and were used in this project as
selfs for backcrossing.
Flash-Grizzle-like lightening at tail-marked young from dominant
white Stralsund Highflyer of the flying type at the author
Selective documentation of platinum-coloured grizzles from a
back-mating project of F1 to Self Coloured Pomeranian Eye
A backcrossing project from
an initial cross of a dominant white Stralsund with a Spread Ash
Pomeranian Eye Crest was documented in 'Critical Issues' part V.
Informative for those seeking empirical findings on the relationship
between dominant white and grizzle variants. From the project, the
following are selected authentic photos of grizzles and mottled
heads, homozygous for platinum, heterozygous for grizzle.
Fig. 3: The barred
heterozygous grizzle females are lighter in colour and resemble
purebred grizzles in some other breeds. Such animals, lacking
Spread, were named White Grizzle by Bonhote and Smalley (1911). The
fuzzy bars may be due to the smoky factor. However, not every
lighter than normal coloured grizzle is thus homozygous for the
Fig. 4: When the
colour spread factor is added, the plumage becomes uniform. At
platin hens dark-grey, at non-platinum black. The markings are
covered. Possibly the check markings are hidden underneath. The
combination of platinum, heterozygous grizzle and Spread results in
Fig. 5: The two cocks are brothers.
One is a platinum bar with grizzle (at the left).
Next to it a platinum self with Spread, but lacking grizzle.
Fig. 6: Finally, two
kittens out of the shown platinum male and one of the grizzle
platinum bar females. A barred platinum coloured juvenile
non-grizzle and a platinum mottled head with Spread.
Bonhote, J.L., und Smalley (1911).
On the colour and colour pattern inheritance in
pigeons, Zoological Society of London, Proceedings, pp. 601-619
Sell, Axel (2012), Pigeon
Genetics. Applied Genetics in the Domestic Pigeon, Achim.
Sell, Axel (2021), Critical
Issues in Pigeon Genetics. What we know and what we believe to know.
Anecdotal, Entertaining and Educational Comments on Open Questions,
Part V, 80 p. Softcover, Achim.
Sell, Axel (2015), Genetik der Taubenfärbungen,
Achim (out of print)
Sell, Axel (2021), Verständnis und
Missverständnisse in der Taubenzucht. Anekdotische, unterhaltsame
und lehrreiche Anmerkungen zu offenen Fragen, Teil V, broschiert, 60
Walker, Joseph R. (1925),
Inheritance of White Plumage in Pigeons, Genetics 10, pp. 593-604