Question to Dr Pilkington from Rachel Jackson:My Greywing yellow (f) and Spangle Skyblue (m) budgies recently had 5 eggs, 2 of which were fertile. One of the young was a Grey-Green Greywing and the other was almost pure yellow, though it wasn't a Lutino. It had dark eyes and you could just see traces of very faint markings on its wings. Its 2 throat spots were white. What variety of budgie would this be?
Answer from John Pilkington: Thanks for your question Rachel. This question looks to be a bit of a puzzle because one of the offspring is Grey-Green and from your description, neither of its parents displays the dominant Grey gene. Since you do not give the parentage of this bird to contradict me, I consider that most likely, you have misidentified the colour of the hen, or alternatively, she mated with another cock other than the Skyblue Spangle you describe. You have since provided me with both a photograph of the hen and a better written description as follows:
The budgie I described as a Greywing Yellow: her body is all a rather drab yellow with extremely pale grey markings on her wings and neck. They look just the same as standard markings apart from being very pale. They seem to have the same pattern. Her 2 main throat spots are white (or pos. very pale blue?) and she has smaller grey ones under them. Her eyes are black, with a white ring around the pupil. I am afraid that I do not know what her parents were. When I first acquired her (at about 2 months old) she looked almost Lutino but has gotten more prominent markings since. She is about 18 months now. And she is certainly not the very bright yellow of a Lutino. Also, I don't know if this has anything to do with it, her feathers do not seem to be as smooth and sleek as other budgies'. They are not held very close to her body, she seems almost fluffy. This is all the time.
From the description and the photographs, the hen is a Grey Yellow or a green series Dilute,, and therefore the mystery is solved: the Grey Green offspring inherited the Grey gene directly from the hen, and genetic theory still works! The other offspring is most likely just a Light Yellow, and has inherited the Yellow gene from the hen but not the Grey gene, and also a Dilute gene from the cock (the cock must therefore be split for White). Since Yellow budgerigars are essentially Green series birds, the Skyblue cock bird's blue genes are recessive to the hen's genes transmitted to the offspring: once again, genetic theory has not been overturned! From your description of the yellow offspring, it is possible that this bird may also carry a Spangle gene (50% chance). Although spectacular colour markings are often displayed by composite varieties (several different mutational genes within the genotype of the individual), when it comes to attempting to improve a specific variety, such composite birds are of little use since they are capable of producing a wide variety of offspring, and only very few will be of the variety that you wish to improve, and then, you have very limited numbers from which to select above average quality specimens.
With regard to the Grey-Green youngster being a Greywing: it is possible that the bird is a Greywing but having seen a photograph of the hen, I think you may be misidentifying a bird as a true Greywing. In your later description of the hen you describe the bird appearing as "almost fluffy'"- from the photograph of this bird she is what is described as "buff" feathered, and incidentally, she appears as a decent specimen.
When describing the feathering of budgerigars, they can be classified as "yellow", "intermediate" and "buff". Please note the term "yellow", when describing feather type, has nothing to do with the colour of the feather. It is possible to have a yellow-feathered Skyblue or a buff-feathered Skyblue, and both birds will not show any yellow colouration whatsoever. Yellow-feathering is very sleek and tight against the bird, which gives a brighter colour, but makes the bird appear small, whereas a buff-feathered bird of the same colour will be less bright and will appear larger in size. The term was originally coined by canary breeders, since the tight feathered birds appeared canary yellow in colour and the fluffier feathered birds appeared buff yellow in colour. budgerigar breeders later adopted the terms to describe feather type. Whilst answering Rachel's question I coincidentally received a related question as follows:
Question from Chris Amaral:: Hello! I have enjoyed following your column on Dolores' page regarding genetics. I noticed that one of your questions dealt with the affect of grey and violet together, which leads to my question: I bred two non visual Grey budgies and came out with 2 Grey offspring out of 14 chicks.
The Hen (Dam): Yellowface Type II Sky Opaline, The Cock (Sire): Violet(nice vibrant violet color) Normal /Cinnamon /Opaline.
Out of 10 babies, they had:
The sex of the Grey birds is unknown, as we sold them young. The Sire (Violet Normal /Cinn /Op), was later mated to a Sky Rec Pied Op and had no Grey offspring out of 14 chicks. The Dam (YF Sky Op), was later mated to a Green Greywing /Rec pied and had no Grey offspring out of 7 chicks. The Dam has since died. We still have the sire. Any ideas how those 2 Greys popped up? (These birds were grey and not mauve!) Thank you!
Answer from John Pilkington:: Thanks for this question Chris. Since you have kept accurate breeding records of both the Yellowface Type II Sky Opaline hen and the Violet Normal /Cinnamon /Opaline cock both as a pair together, and with other partners, and since you have sufficient offspring to test the genotype of both birds in question, the production of two Grey offspring from non-Grey parents, at first glance, does appear strange, as in the question from Rachel Jackson.
However, I consider a different explanation is most likely here. I have heard that a new recessive Grey gene mutation has recently been identified in Australia, and unfortunately I don't know where you are resident. When recessive mutations first occur, phenotypes of the new mutation do not appear until related stock, also carrying the heterozygous recessive genotype, mate and produce the homozygous recessive offspring which display the phenotypic characteristics of the gene mutation. I very much suspect that your Greys are recessive Greys, because two heterozygous recessive parents would on average produce 25% homozygous recessive phenotypes from an infinite number of offspring.
Bearing in mind that from the pairing you describe, only 2 out of 14 offspring display the Grey phenotype, from a sample size of just 14 offspring (considerably smaller than infinity!) this appears about right to me that an average of 25% Grey offspring would have been bred from a much larger number of offspring from the same pairing. In view of the fact that the cock and hen, when paired to different partners, did not produce Grey offspring (although the sample size of offspring bred is relatively small and thus not conclusive). also indicates that both the Yellowface Type II Sky Opaline hen and the Violet Normal /cinnamon /Opaline cock are split for a recessive Grey gene.
If you wish to experiment to see if you do have a recessive Grey gene in your stud: try pairing the Violet Normal /cinnamon /Opaline cock to a few of his daughters (50% of his daughters will be heterozygous recessive Greys if the cock possesses a recessive Grey gene) and these pairings will produce on average 25% Grey phenotypes if there is a recessive Grey gene in your Stud. Keep us all posted on this. The usual dominant Grey gene is referred to as the Australian Grey, but there has previously been a recessive Grey gene, the English Grey. The English grey is thought to be extinct, although it is possible that there may still be a few heterozygous specimens alive today, which if paired together by chance, will produce English Grey phenotypes in similar circumstances to yours Chris. Every allele has an incidence of mutation, and if a Normal gene mutates into, say, a recessive Grey gene once in 10,000 cell divisions, then for every ten thousand egg or sperm cells produced, just one gamete will possess the mutated recessive Grey gene, which may form part of the genotype of just one offspring. In the case of gene mutations which are recessive, then the mutational phenotype will only be seen, if at all, when a gene pool of related birds is established and they commence to interbreed. Even if the English Grey is extinct, then it is quite possible that the same mutation, has occurred again in Australia.
Original text Copyright © 1998, Dr John Pilkington
Editors' note: I regret that Dr Pilkington is unable to answer any further
questions.
Budgerigars Galore Homepage | Contents Index | Beginners | Breeding | Breeding Charts | Diseases | General Interest | Genetics | Links | Management and Nutrition | New Zealand News | Noonan Aviary | Popular Varieties | Rare Varieties | Show Preparation | Specialist Varieties | Tips
Web page copyright © 1999, Dolores Noonan. All rights reserved.
Designed and created by Arcadia WebSite Design.