A Peculiarity
My editorial in the August edition of Budgerigar World told the story of Christine Angus-Smith, who had bred a number of Yellowface blue-whites (dilutes), from a pair of normal looking White-wings. Not surprisingly the knowledge of the fancy came to our aid to explain why. However, two views emerged from the correspondence. The first of these was from Didier Mervilde, who is the Budgerigar World correspondent for Belgium. This is what he had to say:
In answer to the question in BW concerning Whitewings and Australian Yellowfaces. It is perfectly normal to get Dilutes from Whitewings because being recessive bit cock and hen can be split dilute. For the Yellowfaces it is also normal because when you put Yellowface mutant I with Yellowface mutant I the results are 50 % Yellowface mutant 1, single factor; 25% Yellowface mutant 1, double factor and 25% not carrying any Yellowface characters.
The situation is that the double factor Yellowfaces have a white mask so there is no visual difference between a normal blue and the Yellowface. If you pair one of these birds to a blue or grey then Yellowfaces mutant I, single factor are produced and that is what happened with the Whitewings.
So we have an answer but my next question is; If the Yellowfaces were double factors, why weren’t all the offspring produced Yellowfaces and instead of just a few of them?
The next answer came from Pantcho Tomas from Sydney, Australia. This is what he had to say:
Non-disjunction of Chromosomes?
In the August, 1999 issue you cited a breeding peculiarity, whereby a pair of Whitewing Blue budgerigars produced some Yellowface Blue Dilute youngsters in addition to Whiteface Blue Whitewings. This type of anomaly is frequently cited by beginners and novices, but very rare among established breeders. However, when experienced by open breeders, what could possibly be the reason?
I feel the result is possibly similar to that which seems to occur among those who breed double factor Spangles. I have lost count of the novices who claim to have paired a double factor Spangle to a visual Normal and produced a percentage of double factor Spangles. My response, in the past, was always immediate, impossible! However, it seems to happen too often to be discounted as a valid result. So what is the cause of this anomaly?
I have no answer, but would like to pose the following question to the numerous budgerigar geneticists who read Budgerigar World. How common is the occurrence of non-disjunction of chromosomes in avian species? To the layperson, how often do cock birds possess three X, or two X and a Y chromosome? Are these birds sterile, or can they breed? Your friend Christine Angus-Smith may indeed, have a very important cock bird in her possession.
You see, if the cock bird has three X-chromosomes, he may be a double-factor Yellowface. As he only passes on one X-chromosome to his progeny, it then becomes possible for him to produce non-Yellowface offspring. It follows that he should produce Yellowface Blues when paired to any blue series hen, not necessarily a Whitewing.
For simplicity, I have excluded the hen, but could it be that she has an extra chromosome?
Well there we have it, the challenge is thrown. Let’s have some more views please.
Shows
Generally speaking the pattern of shows in the UK is that reduced numbers are being seen on the show bench and because of this, some concern has been voiced as to the value of Challenge Certificates now that there is less competition. I disagree. To be first in a class of 20 compared to being first in a class of 5 is no different if the winning birds are of equal quality. The challenge is to breed good budgerigars - it is no less a challenge if there are fewer people doing it.
Congratulations to John Wolcott and the rest of the team at the Florida Exhibition BS who staged the All-American at the end of September. In conjunction with event they have produced a "Guide To The Color Standards" using a combination of the written word, colour illustration and colour photographs to depict the various varieties of Budgerigar. More than 160 varieties and colours are included in 48 large format pages. Whichever country you live it is a great reference book and is well worth the asking price of $10 plus postage. Further enquiry’s to John Wolcott, 9394D S.W. 97th Lane, Ocala, Florida 34481, USA. Telephone (352) 873-1105.