Comments on the ANBC Yellow Faced Blue Review
Comments on the ANBC Yellow Faced Blue Review
John Mulley, May 2016
Summary: The Yellow Faced Blue review was completed for submission to the ANBC Colour and Standards Committee for its meeting at Hobart in June 2016. It reaffirmed the position of the Yellow Faced Blue Series in the Matrix and the convention of describing all budgerigars by Variety followed by Colour. Colour determination in budgerigars was explained and that formed the basis for the recommendations. Wording for inclusion in the national Standard, including the Penalty and Disqualification Clauses, was revised to be more prescriptive in order to simplify interpretation and remove confusion. Yellow Faced Blue and Double Factor Golden Faced Blue can be categorised as follows: Melanised varieties (for example Normal, Opaline and Cinnamonwing) are devoid of yellow body suffusion so the yellow face is accepted without penalty. This aligns Australia with other parts of the world. Varieties with reduced melanin (for example Fallow, Clearbody and Dilute) are penalised for visible yellow body tinge, so are not competitive unless they significantly exceed their Green and Blue rivals in Type. The de-melanised self-coloured varieties (for example Spangle Double Factor White, Albino and Black Eyed White) are severely penalised for their heavy yellow body suffusion, usually to the extent of 40%. The principle applied is the same as for penalising blue suffusion in these de-melanised varieties, but is far more serious than the blue suffusion since the yellow is usually more obvious. These guidelines have always been implied irrespective of where Yellow Faced Blue has been located in the Matrix. Single Factor Golden Faced Blues continue to be heavily penalised because they depart from the prescribed blue body colour by presenting as a variation of green, due to their underlying yellow body pigmentation.
The two yellow faced mutations have been bred and exhibited in Australia for many years; however, judging by motions submitted to the Australian National Budgerigar Council (ANBC) Colour and Standards (C&S) Committee in 2015 the simple act of correcting their location in the Matrix a few years ago appears to have created confusion among some fanciers. The paler of the two mutations has traditionally been referred to as English Yellow Faced Blue and the brighter one traditionally referred to as Australian Yellow Faced Blue. Geographic naming is not descriptive, so dropping “English” and “Australian” has been recommended, leaving us with the simpler terminology of Yellow Faced Blue and Golden Faced Blue.
Concerns vary from yellow faces taking over the aviary to yellow faces wrecking the established de-melanised varieties. The yellow faces have been present without taking over the aviary and without wrecking the de-melanised varieties ever since I have been breeding budgerigars. Furthermore, the myth persists that the yellow in yellow faces is restricted to the face, but even in the most heavily melanised of the yellow faces, the Normal Yellow Faced Blue, simple observation shows that the shade of the primary body colour is slightly altered by the “yellow face” mutation. This level of effect the Working Party defined as MINIMAL, and as such acceptable, and ensures that the melanised Yellow Faced Blue varieties can compete without penalty for Major Awards. The three colour modifiers dark, violet and grey assist with masking the effect of the underlying spillage of yellow pigment from the mask through the body. I bred yellow faces into the de-melanised varieties more than 20 years ago just to see what they looked like. Yellow face is a misnomer as the yellow tinge always suffuses beyond the face into the body and because of that they have not generally been exhibited. This applied when yellow faces were previously located between the Pieds and Fallow in the Matrix. Yellow Faced Blue never took over the Pieds, Spangles and Crests at that time, nor should they take over any of the additional varieties located below them with their current position in the Matrix, with the other colour series Green and Blue.
The series of motions in 2015 imply that changing the position of yellow face in the Matrix has created a sudden desire to breed and bench yellow face into Black Eyed White, Albino, Spangle Double Factor White, Clearbody blue series, Lacewing whites and Fallow blue series. The way they are judged in relation to descriptions of yellow face in the Standard does not encourage that, and has not changed, so should not be confusing to judges. Clubs need to educate their members if they imagine otherwise. The yellow body suffusion remains heavily penalised
on the show bench (by up to 40% ), just as it has always been [Strictly speaking 40% is allocated to “colour and varietal markings”, not just “body” colour. Therefore, as an example, a well
marked lacewing could lose a considerable portion of the 40% due to yellow wash but must be awarded points for it’s markings, spots and perhaps face and mask also – Editor ,Ben Hale] .
There is nothing to stop anyone benching these birds, because the Matrix is designed to accommodate every recognisable variety, but if they do bench these birds they have to be aware
of the instant starting penalty for colour. Only after overcoming that with vastly superior Type can they win the class. As for yellow faces taking over the aviary, if that happens it could only be brought about if WE as breeders use yellow face blues as parents in too many of the crosses that WE set up. Actively introducing yellow faces into the above de-melanised varieties makes no sense other than if we were breeding for the pet trade or interested in genetic experimentation in the backyard. Sometimes one might buy a Green Series outcross split for undeclared yellow face, but that isn’t new. I first saw that happen more than two decades ago.
One of the motions suggested introduction of Yellow Face AOSV positioned at the bottom of the Matrix, to keep yellow face out of varieties other than Normal. That is already achieved
where necessary in the de-melanised varieties by judges applying penalties in line with the Standard. Corrupting the Matrix would undermine its utility and cause confusion since it
contradicts the way the Matrix is routinely applied to exhibition budgerigars and explained to new members. The Matrix is designed for consistency in interpretation and simplicity of usage
for show managers, exhibitors and judges alike.
There are already 81 birds to be housed and transported by each State/Zone to the National Show. That number of birds is not trivial for both the travelling states and the logistical demands
now being placed on the host state. We do not need a heterogeneous collection of varieties added as a new class bound together only by their colour, which would then filter down to state and
club show schedules. The ANBC have already created two classes for Opaline when it would be preferable to concentrate on breeding for one class of clear headed Opaline that would match the
Standard. Then they introduced a second class for Spangles for breeders who could not breed Normal spangles. Clearwing and Greywing breeders manage to keep Opaline and Cinnamonwing out of those varieties for the purpose of exhibition. The same should be applicable to anyone needing to keep Yellow Faced Blue out of the de-melanised varieties.
The yellow face topic as a whole was too complex to easily resolve at just one annual meeting which prompted the ANBC Delegates to establish a Working Party to compile a Yellow Face
Review for presentation to Council in Hobart in June 2016. This approach was previously used in updating what was previously the confused presentation of the Pied Standard. Broad Terms of
Reference for the Review were as follows:
- Genetic correctness is essential
- Formatting to be in line with the current ‘Standard’
- Colour descriptive and wording is to be easily understood by all
- The use of technical descriptive/terminology should be minimal
- Actual testing by visual representation should be a goal
- A complete formatted presentation to Council is to be the end goal
- A summary with descriptive comments on outcomes would also assist
- A quarterly update to the Executive until finalized is also requested
The Working Party consisted of the national C&S Coordinator Peter Glassenbury as the central liaison with the four nominated State/Zone representatives being Peter Thurn BCV, Neale
Love SQBBA, John Mulley BCSA and Jean Painter BSNSW. Between them they represent well over a century of experience breeding and exhibiting budgerigars, all are Major Award Judges
with four of them accredited National Judges. The Matrix and classes in all club, state and national show schedules are based on gene mutations so it was advantageous to have two
members of the group with postgraduate qualifications and experience working in animal genetics. Following extensive deliberations Peter Glassenbury submitted a complete review to
the ANBC in correct C&S format.
The following is a rephrased version based on the official C&S submission with some of the wording retained but in a style aimed at club magazines. I have added some additional comments of mine and these may or may not be the views of the other members of the Working Party who deliberated on the Yellow Face. The official C&S submission by the Working Group was more succinct and was presented in the C&S format compatible with inclusion direct into The Standard.
What gene determines body colour in budgerigars?
Consider firstly, for simplicity, the Normal variety at the top of the current Matrix. All of them have the same gene or genes that determine the expression of melanin giving the Normal its characteristic pattern of markings. Furthermore, all of them have the same set of developmental genes that determine the structure of the feathers distributed over the body of the bird. Feather structure and the distribution of melanin within are two of the three components that determine body colour in budgerigars. The third component in combination with the above two is the yellow pigment psittacofulvin which from now on will simply be referred to as yellow pigment. Since the amount of yellow pigment is the one variable that changes the primary colour of the body that we see in the Normals, the gene that controls production of the amount of this yellow pigment will now for simplicity be referred to as the colour gene. The distinction between Variety and Colour is recognised by the hierarchical naming convention where we describe budgerigars first by their Variety followed by their Colour; for example, Normal sky blue, Clearwing light green, Cinnamonwing grey green, Opaline yellow faced grey, Spangle double factor white, etc. etc.
How does the yellow pigment produced by the colour gene affect feather colour?
For anyone who might wish to delve deeply into the technical basis for how the interaction between melanin, feather structure and yellow pigment affect colour the Working Party referred to, as an example, the following research paper published in 2013 in the Journal of Experimental Biology volume 216, pages 4358-4364 entitled Spectral tuning of Amazon parrot feather coloration by psittacofulvin pigments and spongy structures, by the research scientists Jan Tinbergen, Bodo D. Wilts and Doekele G. Stavenga. The psittacofulvin referred to in this article is the exact same chemical substance as the yellow pigment in budgerigars. Expressed simply, we see blue and black in the feathers of the Normal budgerigar because of the distribution across the body of melanin and barb and barbule structures within the feathers. The small feather barbs and barbules together with melanin embedded within the feather reflect blue light so we see a blue bird. Add the yellow pigment to these structures and this pigment acts as a spectral filter. The yellow pigment absorbs blue light on its way into and on its way out of the feather barbs. What is left is reflected green light, which we see as a green budgerigar. Thus, green in budgerigars is a combination of yellow pigment superimposed upon what would otherwise be blue determined by the combination of feather structure and the distribution of melanin in the feathers.
How does the genetically determined variation in amount of yellow pigment produced from the colour gene affect feather colour?
Firstly, it needs to be understood that apart from sex-linked genes in female budgerigars (for example Opaline, Cinnamonwing and Ino) all genes exist in pairs because the chromosomes that
carry the genes are paired in each nucleated cell in the bird’s body. The Blue mutation is recessive to Green so it is only expressed as a Blue bird in its double factor form (meaning that at the colour gene both members of the gene pair are Blue). The Blue mutation in two doses shuts down production of yellow pigment so we see blue light reflected from the feathers due to the combined effect of feather structure and the distribution of melanin within the feathers.
The Yellow Faced Blue mutation, dominant to the Blue mutation but recessive to wild type Green, inhibits production of much but not all of the yellow pigment, just leaving a pale residual amount of yellow pigment mainly spread across the face, head and secondary tail feathers when in combination with the Blue mutation, which it is assumed contributes none of the yellow pigment. It appears that the second dose of the Yellow Faced Blue mutation in the double factor form further inhibits production of the yellow pigment and thus a white faced bird with no visible yellow pigmentation is the result. Such a bird is obviously benched in the Blue class because that is how it appears and we know that this appearance as seen by the exhibitor and by the judge can be determined by two different genotypes of the colour gene.
The Golden Faced Blue mutation (previously known as the Australian Yellow Faced Blue), also dominant to Blue but recessive to Green, may be visualised as a much milder mutation of the same colour gene and takes away less of the yellow pigment than the Yellow Faced Blue mutation when it is in combination with the Blue mutation. Hence, in the Single Factor Golden Faced Blue there is enough yellow pigment left to cause easily seen green body suffusion, largely masking the pure blue body colour, after the bird goes through its first moult. The effect increases as the bird ages. The suffusion can to some extent be masked by the dark and violet colour modifiers, but for those who breed and keep this variety they are easily recognisable as Single Factor forms of the Golden Faced Blue.
It appears that the second dose of the Golden Face mutation in the Double Factor Golden Faced Blue takes away more of the yellow body suffusion as compared with the Single Factor form. We suggest that less yellow pigment is removed in the Double Factor Golden Face than in the Single Factor (English) Yellow Face with the yellow on the face and head remaining more intense (golden) than on the (English) Yellow Face. The Double Factor form of the Golden Face is the only form of the Golden Face that retains the blue body colour and as such is the only form that can be exhibited without heavy penalty for colour directed against the yellow suffusion, seen as green or grey green in the Single Factor Golden Faced Blue.
To summarize, the Yellow Face, Golden Face and (Whiteface) Blue mutations occur at the same gene and all differentially effect colour by exactly the same mechanism. The colour differences are determined only by the degree of removal of the yellow pigment as determined by the activity of the one gene responsible for production of the yellow pigment. That was the reasoning a few years ago behind the ANBC correcting the position of the Yellow Faced Blue in the Matrix, which amounted to grouping all of the colours and colour modifiers together. As an extension to that, it is a biological fact that all of the varieties below the Normal can also be bred in all four colours with their additional three colour modifiers. Blue, Yellow Faced Blue and Golden Faced Blue are all mutations of the same gene and all recessive to wild type Green so logically all need to be treated the same insofar as positioning the colours in the Matrix is concerned.
A precise mechanistic explanation for the above must await determination of the DNA sequence of these gene mutations and then how the small differences in the mutant DNA sequences translate to the expression of the amount of yellow pigment produced. Whether Blue occurred before Yellow Faced Blue, or vice versa (both would have remained hidden as recessive mutations long before they were seen), or whether one mutated to the other or whether both mutated independently direct from Green is not known. Scientists have recently sequenced the large budgerigar genome but as yet none of the mutant DNA sequences that underlie any of the Colours or Varieties set out in the Matrix have been characterised. Apart from the gene that determines the four primary colours referred to above, separate genes modify these primary colours. The colour modifiers are Grey, Dark and Violet and like the primary colours can be present in all varieties. Prior to the correction to the position of the yellow faces in the Matrix Yellow Faced and Golden Faced Blue were the only Colours not officially recognised as such, and not correctly placed.
How do Yellow Face and Golden Face mutations affect body colour in the melanised varieties?
Comparison of any Normal in the Blue Series against the same body colour in the Normal Yellow Faced Blue Series reveals a slight difference in colour purity caused by an underlying spread of yellow pigment in the Yellow Faced Blue Series. This is evident as an unmistakeable heavy yellow tinge in the self-coloured varieties where there is no melanin, and is somewhat evident in varieties with reduced melanin. This is part of the characteristic expression of “yellow face” and can never be eliminated in these varieties. The same spread of yellow pigment is always present in the Normal variety and other melanised varieties but is largely masked by melanin, with additional help from grey, dark and violet colour modifiers when present; hence, the very slight effect on the purity of body colour compared with the non-Yellow Faced Blue Series is what was defined by the Working Group in the Review as MINIMAL. This subtle effect was not taken into account in the wording of early versions of the Yellow Faced Blue Standard. Minimal effect on body colour is a characteristic feature of this mutation so is not to be penalised in the melanised varieties. Suffusion beyond “minimal” is penalised in proportion to the departure from minimal, just as degree of flecking in the Normal, Cinnamonwing and Opaline is penalised, the amount of blue suffusion in Albinos and Double Factor Spangle Whites is penalised, the amount of green suffusion and departure from buttercup yellow in Black Eyed Yellows is penalised and the loss of wing clarity in Clearwings is penalised.
The same phenomenon of minimal yellow suffusion applies to the Double Factor Golden Face but the effect of the underlying yellow pigment in the Single Factor Golden Face is strongly evident, only muted to some extent by its combination with the dark, violet and grey modifiers. Even so, the colour after the first moult in a Single Factor Golden Faced Cobalt or Violet is nothing like the Cobalt or Violet seen in the non-Yellow Faced Blue Series despite claims to the contrary that the Single Factor and Double Factor Golden Face can’t be easily distinguished from each other.
Yellow Face and Golden Face Hybrids
The Working Party was aware that some breeders are mixing the Yellow Faced Blue and Golden Faced Blue to produce hybrids. We were unable to get firm information on why they were doing this or firm information on the appearance of hybrids, so this was not included in the Review. We could speculate that body colour might be blue due to the combined effect of the two mutations reducing the yellow body pigmentation and that the yellow on the head might be paler or at least similar to that seen in the Golden Faced Blue if the latter was completely dominant to Yellow Faced Blue. If it turns out that the hybrids cannot be easily distinguished from the Double Factor Golden Faced Blue by a judge, then the class may need to be discontinued.
The point in introducing Golden Faced Blue into the National Show was to preserve this mutation from extinction. The higher degree of difficulty in breeding the Double Factor Golden Faced Blue meant that it was not competitive against the easier to breed Yellow Faced Blue which took over the yellow face class after the English imports. Prior to the English imports into Australia in the late 1980’s the yellow face on the show bench was the Double Factor Australian Yellow Faced Blue, the bird referred to above as the Double Factor Golden Faced Blue. Back then, breeders and judges had no problem distinguishing between the Single Factor and Double Factor forms because only the Double Factor form had a blue body. After the English imports, the English Yellow Faced Blue, the bird referred to above as the Yellow Faced Blue, completely displaced the Double Factor Golden Faced Blue on the show bench. As far as I know, it is only since the Golden Faced Blue has been introduced as a separate class in show schedules, many years after the advent of the English imports, that breeders have recently started hybridising. If the hybrids are not easily distinguishable from the genuine Double Factor Golden Faced Blue there can be one of two outcomes. One outcome would be to delete Golden Faced Blue as a separate class, and merge them back into a single category of yellow face which includes the “English” form but specifying buttercup yellow, as was the case in the past. Another possible outcome would be to live with the hybrids and be satisfied that this at least saves the Golden Faced Blue mutation from extinction. Justification for this second option might be that we have already accepted hybrids since the advent of the English imports, between the Yellow Faced Blue mutation and the Blue mutation, which is what the Yellow Faced Blue actually is. So the whole area is more complicated than might have initially been realised, and in the end show managers can only set the classes, and judges can only judge what they can see in front of them. What remains to be done is for someone with knowledge of these hybrids to compile a detailed description to enable a decision to be made on the practicality of separating the two yellow faces on the show bench.
Albino, a further example of the Complexity
By definition, the pink eyed Albino mutation blocks the synthesis of melanin through deactivation of the gene that encodes the enzyme tyrosinase. Normally tyrosinase acts on the amino acid tyrosine in a biochemical pathway leading to melanin. Take away melanin when tyrosinase has been deactivated and in the blue series bird that leaves us with our familiar white feathered and pink eyed Albino budgerigar. Take away the melanin from the green series bird with the inactive tyrosinase and we still technically have an Albino due to deactivation of tyrosinase, but modified by heavy yellow suffusion retained by the wild type activity of the unrelated colour gene that produces the yellow pigment. That bird is the Lutino. Both were exhibited together as the Ino variety until divided into separate Ino classes based on colour at the National Show some years ago. That leaves us with no class for the Albino associated with limited production of yellow pigment, namely the Albino “yellow faces”. There are two solutions: one is to create another class for these birds with intermediate yellow pigmentation, or penalise them heavily for colour if entered into either the Albino (because of their yellow suffusion) or Lutino class (because the yellow is too pale). The pragmatic approach is to maintain the status quo, rather than introducing yet another class, and to regard them as Albinos since they are deficient in tyrosinase, which is the biochemical definition of albino. These yellow suffused Albinos or pale Lutinos were previously heavily penalised when entered into the Yellow Faced Blue class. That should not change if entered into the Albino class after the Yellow Faced Blue position in The Matrix was corrected a few years ago. Scientifically, the Yellow Faced Albinos will always be pink eyed Albinos.
The same argument can be used for the other de-melanised varieties or varieties with reduced melanin with mechanisms not involving defective tyrosinase. They were never accepted on equal terms with green and blue when judged as Yellow Faces. Maybe some time into the future they will be, but currently there is insufficient support from the majority of fanciers for departing from the traditional green (yellow) and blue (white) presentations on the show bench for the demelanised varieties. Yellow face has always been allowed in the Pieds and Spangles and it has not “taken over” in those varieties because the genetic knowledge to guard against that is extremely simple, if that is the goal of breeders.
The MATRIX in the Australian Standard
The purpose of the Matrix is to concisely display a placement on the show bench for any of the vast number of possible combinations of the known mutations. The simplicity of the Matrix in achieving its aim, without increasing its complexity with exceptions, is the envy of many countries throughout the world. Simplicity and ease of understanding allows show managers to compile show schedules with classes listed in a prescribed order and provides exhibitors with the guidance for placing entries into the correct class, irrespective of Varietal and Colour combinations. The document is utilized by the ANBC as a basis for exhibition at the National Championship Shows. Any club can vary the scheduling of classes at their shows to meet their particular needs as is now the case with the Pied Society, for example. But the way classes are included on show schedules should not be confused with the way the Matrix needs to be compiled for consistency of interpretation.