Australian Pied Budgerigar Mutation
   HOME

TheInfoList



OR:

The Australian Pied budgerigar mutation is one of approximately 30 mutations affecting the colour of
budgerigar The budgerigar ( ; ''Melopsittacus undulatus''), also known as the common parakeet or shell parakeet, is a small, long-tailed, seed-eating parrot usually nicknamed the budgie ( ), or in American English, the parakeet. Budgies are the only spe ...
s. It is the underlying mutation of the Banded Pied variety.


Appearance

All pied budgerigars are characterised by having irregular patches of completely clear feathers appearing anywhere in the body, head or wings. These clear feathers are pure white in blue-series birds and yellow in birds of the green series. Such patches are completely devoid of black melanin pigment. The remainder of the body is coloured normally. File:Parakeet.JPG, Two young Australian Pieds, a Cobalt and a Yellow-face II Cobalt (?) File:Parakeets.jpg, Opaline Cobalt Australian Pied cock File:Budgerigar Norway -01.jpg, Cobalt Australian Pied hen File:Wellensittich Vogelpark.JPG, Cobalt Australian Pied cock with a Grey-Green cock The Australian Pieds are very similar in appearance to the Clearflight Pieds, with a nape spot, clear areas on the wings and a clear area on the breast. They differ from the Clearflight Pied in the nape spot, which is not always present, and in their feet, which are usually pink. But the main point of difference is in the clear area of the body, which in the Australian Pied is located in the middle or lower breast, with the upper breast being always normally coloured, so that there is a clear division between the mask and the breast, just as in normal birds. In the Clearflight Pied the clear area on the breast, if present, is almost always adjacent to and running into the mask. Australian Pieds often have larger clear areas on the wings than Clearflight Pieds, with all
primaries Primary elections, or direct primary are a voting process by which voters can indicate their preference for their party's candidate, or a candidate in general, in an upcoming general election, local election, or by-election. Depending on the c ...
and many secondaries often clear, but this cannot be taken as a distinguishing feature as the pied areas are very variable in extent in both mutations. Australian Pieds have the usual white iris ring when adult, distinguishing them clearly from Recessive Pieds, which have no iris ring at any age. In the Australian Pied the clear area often takes the form of a band running across the breast. Birds with such bands are highly prized, especially if the band is clear, sharp and symmetrical, and the feature is now quite common and distinctive due to selective breeding. Such birds comprise the Banded Pied variety.


Historical notes

Many isolated appearances of pied or variegated budgerigars were reported in Britain, in continental Europe and in Australia in the late 1920s and early 1930s, but reliable reports of breeding results and detailed descriptions of their appearance during that period are rare. One of the earliest reports of the appearance of a budgerigar which could have been an Australian Pied was of a bird owned by W G Bowden - it had a clear nape spot and its breeding behaviour clearly showed a dominant inheritance pattern. Mr Bowden obtained or possibly bred the bird in 1931 - he did not report its source. The bird, a cock, was basically a Light Green but it had 'a yellow patch on the back of the head, another on the base of the rump' and 'a yellow streak, about a quarter of an inch in width, from the left wing butt to halfway across the breast'. A number of its flights were reported to be white or yellow. When mated to an unrelated hen in 1933 this cock produced 14 young over three nests, of which 5 showed some clear feathers on the nape of the neck. This could have been the first report of a Clearflight Pied or an Australian Pied; which of these it was is now impossible to tell as the only description available matches both types of Pied. Several similar pied birds were reported around the same time in Germany, bred by Herr Krabbe and separately by Herr Schucke, by Madame Lecallier in France, by G Wilson and T L S Dooley in England, in Holland and in Scotland, but detailed descriptions and the mode of inheritance are unknown. The present-day Australian Pieds, including the Banded Pied variety, are believed to be descended from a strain first established in
Sydney Sydney ( ) is the capital city of the state of New South Wales, and the most populous city in both Australia and Oceania. Located on Australia's east coast, the metropolis surrounds Sydney Harbour and extends about towards the Blue Mountain ...
in 1935 by Keith Ings.Rogers (1990) p 76 et seq They were first imported to Britain in 1957/8, when Mr A M Cooper of
Caerleon Caerleon (; cy, Caerllion) is a town and community in Newport, Wales. Situated on the River Usk, it lies northeast of Newport city centre, and southeast of Cwmbran. Caerleon is of archaeological importance, being the site of a notable Roman ...
, South Wales, bought two such birds, a Pied Green and a Pied Grey, both cocks, from a dealer in Bristol. Most of the Australian Pieds in Britain are descended from the Cooper strain.


Genetics

The Australian Pied
allele An allele (, ; ; modern formation from Greek ἄλλος ''állos'', "other") is a variation of the same sequence of nucleotides at the same place on a long DNA molecule, as described in leading textbooks on genetics and evolution. ::"The chro ...
is dominant over its wild-type allele, although with less than 100%
penetrance Penetrance in genetics is the proportion of individuals carrying a particular variant (or allele) of a gene (the genotype) that also express an associated trait (the phenotype). In medical genetics, the penetrance of a disease-causing mutation is t ...
. The extent and distribution of the clear areas shown by both single-factor (SF) and double-factor (DF) Australian Pieds are variable. The range of variability of the two
genotypes The genotype of an organism is its complete set of genetic material. Genotype can also be used to refer to the alleles or variants an individual carries in a particular gene or genetic location. The number of alleles an individual can have in a ...
appears to be identical, so it is not possible to determine the genetic make-up by considering the extent of the clear areas. In both single- and double-factor birds this variability ranges from no clear feathers at all, via just one or two clear feathers, to over half the body area affected, although the clear areas in cocks tend to be larger than those of hens. The Australian Pied gene is located on one of the
autosomal An autosome is any chromosome that is not a sex chromosome. The members of an autosome pair in a diploid cell have the same morphology, unlike those in allosome, allosomal (sex chromosome) pairs, which may have different structures. The DNA in au ...
chromosomes A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are ...
. There is no known linkage of this gene with any other mutation. There is no universally accepted genetic symbol for either the
locus Locus (plural loci) is Latin for "place". It may refer to: Entertainment * Locus (comics), a Marvel Comics mutant villainess, a member of the Mutant Liberation Front * ''Locus'' (magazine), science fiction and fantasy magazine ** ''Locus Award' ...
or mutant allele, so the symbol ''Pa+'' for 'Pied, Australian' will be adopted here for the wild-type allele at this locus, and the symbol ''Pa'' for the Australian Pied mutant allele. The factors governing the extent and distribution of the residual pigmentation are not known, although it is likely that at least some factors are sex-linked due to the different ranges in variability of the sexes.Taylor & Warner (1986) p 88 Unlike the Clearflight Pied, the Australian Pied does not produce any Dark-eyed Clears when crossed with the Recessive Pied.


Notes


References

* *


External links


World Budgerigar Organisation (WBO)

MUTAVI
{{DEFAULTSORT:Australian Pied Budgerigar Mutation Budgerigar colour mutations