|Posted by ramboooo on April 22, 2010 at 6:52 AM|
Mutations in Agapornis roseicollis
As previously mentioned we can expect colour mutations by alterations of eumelanin, psittacine, distribution of pigments (eumelanin or psittacine) and feather structure. This is also the case in mutations of roseicollis. Let us go through the points once again.
Alteration in eumelanin distribution:
Recessive and dominant pied
Alteration of feather structure:
Manifestation originated bij crossing-over:
The Ino factor (sex-linked)
The ino factor reduces visible eumelanin completely. As well as in the plumage, the eyes, the legs, toes and nails. Combined with a green bird this will result in a pure yellow bird, the legs are pink coloured and, typical for this mutation, red eyes. The colour of the rump is white.Because the psittacine is unaffected by this mutation, the red of the mask stays unaltered. In roseicollis this mutation is sex-linked and we refer to it as SL ino.
In combination with other mutations:
Lutino (wildtype + ino)
Orange face lutino
Pale headed lutino
This mutation causes a 60% reduction of the visible eumelanin resulting in a yellow bird with a green bloom all over the body. Flight feathers are light grey. The rump is partially affected.Legs, toes and nails are pink coloured. The mask is unaffected. The basic type is called pallid green.
These birds have red eyes at hatching that darken into deep dark brown after a day or eight. Pallid inherits also sex-linked and originated in Australia, that is why one referred to these birds as “Australian cinnamon”. This mutation inherits as a sex-linked character, just like its cinnamon and ino counterpart, however, mind that the pallid allele is situated at the sex-linked ino-locus. That means that we actually have to deal with a multiple allolomorph of this locus, to put it simple, another mutation of the ino-locus showing a less dramatic effect than ino.
If we breed a combination of pallid and ino, and only the male offspring can have such combination, we obtain an intermediate colour shade between pallid and ino and not wildtype coloured birds. This proves that pallid is allelic to ino and we refer to these cocks as pallidinos. Hens can never be pallidinos because they can never be split for a sex-linked character. When we mate such ‘pallidino’ cock to a green hen we can expect pallid hens, ino hens, green/ino cocks and green/pallid cocks. This can be very confusing for the average breeder. Note that these ‘pallidino’ cocks look like too light coloured pallids and therefore are not in demand for shows.
Until recently the name isabel was used for this mutation, however, it turned out to be unsuitable for this species. Isabel is in use in the canary community for a sex-linked combination of brown (cinnamon) and agate (pallid). Agate in canaries is the equivalent of pallid in roseicollis. The isabel canary is derived from a crossing over between brown and agate. The fact that a separate name was given to a mutation combination was very confusing and the impression was given that we had to deal with a separate mutation and that is not the case.Separate names for mutation combinations should be avoided, however, there is one exception; the lacewing Budgerigar. As long as we realize that this is in fact a combination of cinnamon and ino, we could live with that. (The term lacewing justifies the phenotype only in this species and not in other psittacine species).(top)
An eumelanin mutation as well, however, not a mutation that reduces the amount of eumelanin. This mutation alters the colour of the eumelanin into brown instead of black. Black eumelanin absorbs almost all daylight, however, brown eumelanin reflects more light and shows a brown colour. The result is a brownish green bird with brown flights and pink coloured legs and toes. The mask stays unaltered because the mutation does not affect psittacin. Typical for this mutaton is that all yougsters have red eyes at hatching. The eyes darken to dark brown after about 8 days. The mutation inherits sex-linked recessive. The basic type is the cinnamon green.
In combination with other mutations:
Cinnamon green, cinnamon D green, cinnamon DD green
Orange face cinnamon green etc.etc.
Cinnamon turquoise, cinnamon dark turquoise, cinnamon double dark turquoise
Cinnamon aqua, cinnamon dark aqua, cinnamon double dark aqua(top)
Bronze fallow (FKA type I)
In this mutant this is also an alteration of the colour of the eumelanin. Instead of brown the eumelanin has a grey brown appearance. This can be observed especially in the flight feathers. In common it is of a somewhat lighter shade than cinnamon caused by smaller eumelanin granules produced by this mutation. Eumelanin is almost absent in the legs, toes and eyes and therefore these birds have pink legs and red eyes. The rump has a dullish blue colour. The psittacine stays unaffected leaving the mask unaltered. At first sight this bird can be mistaken for a cinnamon, however, the clear red eyes and the paler back of the head indicate the typical fallow mutation. This mutation inherits recessive.
The first fallow roseicollis originated in West Germany in the aviaries of mr. Bodo Ochs. That is why one referred to these birds as West German fallow in roseicollis. This type of fallow might be allelic to the NSL ino-locus, however, this should be proven by testmatings. The basic type is the lightgreen bronze fallow.
Combinations with other mutations:
Bronze fallow green, bronze fallow D green, bronze fallow DD green
Orange face bronze fallow green, etc, etc.
Bronze fallow aqua, bronze fallow dark aqua, bronze fallow double dark aqua (top)
Pale fallow (FKA type 2)
Almost equal to the bronze fallow but there is some difference. The greyish brown eumelanin content is lesser than in the bronze fallow resulting in a paler coloured fallow. An olive yellowish bird with a dull blue rump and ruby red eyes. Not only the clear red eyes are typical for this type of fallow but also the greenish shade at the lower abdomen. Legs, toes and nails are pink coloured. These fallows inherit recessive. This type originated in East Germany, which explains its former name, the East German fallow. The basic type is pale fallow green.
Combinations with other mutations:
Pale fallow green, pale fallow D green, pale fallow DD green
Pale fallow orange face green, etc, etc.
Pale fallow turquoise, pale fallow dark turquoise, pale fallow double dark turquoise
Pale fallow aqua, pale fallow dark aqua, pale fallow double dark aqua (top)
Alteration in eumelanin distribution:
The first edged diluted birds originated in the U.S.A. That is why people referred to these birds as “American golden cherry” at that time, which was in fact a derivative from “American cherry head” (Cherry head was the English name for roseicollis). Nowadays we refer to such bird as Edged diluted green (basic type).Edged dilute is a mutation of the eumelanin distribution. In this mutation we observe a typical edged effect on the wing coverts. This is caused by a normal distribution of eumelanin only at the edges of the feathers and a poor distribution in the remaining part of the feather. The reduction in the poor pigmented areas is about 60% resulting in a lightgreen-yellowish area. The outer ridge of the feather contains much more eumelanin and is therefore darker causing the “edged” effect. The same effect is seen in the flight feathers. A further reduction of eumelanin in other parts of the plumage is equally distributed, about 50%, and is equivalent to pastel birds. Only the wing coverts and flight feathers show the edged effect. The rump of these birds is bleached. Legs and nails are light grey. The name is based on the pastel body colour and the edges on the wing coverts. This mutation inherits as a recessive character. By adding one or two dark factors one becomes an edged diluted dark green or an edged diluted olive green. This mutation can be combined with several other psittacine mutations such as orange face or pale headed. These combinations are indicated as orange faced edged diluted green or pale headed edged diluted green. In combinations with turquoise or aqua one refers to it as edged diluted turquoise or edged diluted aqua. One addressed these birds formerly erroneously as “American silver cherry” or even “silver”. Commercially it is a good sounding name, however, it did not tell anything about the geno- and phenotype of these birds. These names should be abandoned as much as possible. (top)
In this mutation the eumelanin has disappeared for almost 80 to 90% in the entire plumage.The result is an almost completely yellow coloured bird. However, it is not bright yellow because of the presence of few eumelanin in the feather barbs.The first dilute roseicollis originated in Japan. Therefore one referred to these birds as Japanese cherry or Japanese golden cherry. In dilute roseicollis one can also observe a lighter coloured rump. The barbs of the rump feathers of roseicollis lack the barbules at the top of the feathers for about 3 mm. The barbules of the rest of the rump feathers contain eumelanin for about 50% in the wildtype. This explains the rather dark blue colour of the rump in wild type roseicollis. If the reduction is about 90%, like in dilutes, the colour will be pale blue. The eumelanin content is very much reduced resulting in a lesser absorbtion of the daylight and a lighter blue colouration.The mask of roseicollis is, as mentioned before, composed with feathers of the “pride” type, however, the mutation has no effect in this area and the red colour stays preserved. The legs and toes stay almost unaffected in both mutants, they are like the flight feathers, light grey in appearance. Dilute inherits recessive.
Combined with other mutations:
Dilute green, dilute D green, dilute DD green
Orange face dilute green,.........
Dilute turquoise, dilute dark turquoise, dilute double dark turquoise
Dilute aqua, dilute dark aqua, dilute double dark aqua (top)
Pied: the partial absence of eumelanin, unequally spread into several areas of the complete plumage. A way to describe this kind of mutation the best. The result is a bird with unpigmented patches or areas. The first one is the dominant pied roseicollis first bred in the USA. The first announcements were made in the early thirties, however, it was not before the early sixties that the first detailed description was published.This type of pied can vary from a few pied feathers till an almost complete absence of eumelanin. The mask is smaller in appearance in this mutation. Although these birds have a dominant inheritance, it is hard to say whether there is a clear difference between SF and DF birds or not.The basic type is pied green.
Combinations with other mutations:
Pied green, pied D green, pied DD green
Pied orange face green, etc, etc.
Pied turquoise, pied dark turquoise, pied double dark turquoise
Pied aqua, pied dark aqua, pied double dark aqua (top)
The recessive pied mutation originated in Australia and shows an almost completely yellow bird. We might say that this type of pied causes a 95% absence of eumelanin. The colour of the flight feathers, legs, toes and nails can vary from grey till completely dilute. In most cases the rump colour is totally affected and sometimes a light green shade is seen at the upper rump or the lower back. In spite of the fact that pied is a mutation affecting indirectly eumelanin distribution, one can also observe a smaller mask in this type of pied. Split birds can be recognized in most cases by a pied spot at the inner side of the thighbone. (top)
Dark eyed clear (DEC)
Just like in Budgerigars we are able to breed completely yellow birds from a combination of dominant and recessive pied. From a genotypical point of view these birds are in fact DF dominant pied recessive pieds (as a formula Pi / Pi s / s). If we mate such bird to a wild type bird, all offspring will be SF dominant pied split recessive pied. (top)
The best known psittacin mutant is the blue coloured bird. In such bird the yellow psittacin is completely absent. These blue birds are best recognized and therefore much easier understood. However, in roseicollis the matter is different because a genuine blue mutant does not (yet) excist in that species. There are turquoise and aqua mutants. These are colours that verges on blue but it is not pure blue.Other psittacine mutations are orange face and pale head altering the colour of the psittacine and also opaline extending the psittacine on the head. (top)
In an aqua bird the yellow psittacin is reduced by approximately 50%. That means that the yellow colour in the cortex of the plumage is not as yellow as it is in the wild type. If we dilute yellow paint for about 50% we will also obtain a lighter yellow colour. The blue light rays, aroused in the spongy zone, pass through a light yellow “filter” producing a colour that is not green and not blue, it is more in between. That is why this colour is called aqua. Not only the yellow psittacine in the plumage is reduced, also the red psittacine of the mask. The red becomes about 50% paler. Therefore the aqua roseicollis gets its typical pink mask. Legs, toes and nails stay unaffected. Only eumelanin is responsible for the colouration of the legs and toes. Aqua inherits as a recessive. This colour shade can be combined with almost every other mutation; cinnamon, pallid, edged, dilute and fallow. Combined with orange face it will result in a aqua bird with a ‘yellowish’ mask. This combination is not of any use for shows because it is neither accepted nor in demand. Combinations with the dark factor is possible, one refers to such birds as aqua (basic type), dark aqua (one dark factor) and double dark aqua (two dark factors). (top)
Turquoise (pale face)
In turquoises there is a reduction of 80 sometimes even 90% of the psittacine in the whole plumag. The psittacine in the cortex becomes very light yellow and by the action of the blue rays in combination with the pale yellow psittacin, we see a bird that is much more “blue” than the aqua. Except for the wing coverts, there is still a green shade, even green patches are visible in the plumage because the reduction in those patches is obviously only 50 till 60%. The psittacine still present, makes the wing coverts more turquoise coloured, in contrast to the almost blue body. In the mask the red psittacine is reduced for about 90% leaving it almost white. However, if we take a good look we can still observe a light pink shade at the front head. That is because there is still 10 till 15% red psittacin present in that area. A true white mask can only be achieved if the psittacin is completely lost, thus in a genuine blue bird (think of the blue Fisher). This mutation was formerly named “white face” for that reason and is now renamed to turquoise. This colour can be combined with almost every other colour in the blue series, just like the turquoise (except for orange face). Combined with the dark factor we refer to these combinations as dark turquoise and double dark turquoise. The inheritance is also recessive. (top)
Let us make perfectly clear that this is not a separate mutation but a mutation combination. Turquoise and aqua are both alleles of the bl-locus. In other words, they are multiple alleles. If we combine a turquoise and an aqua, the result will not be a green bird split for turquoise and aqua, but a bird with an apple green phenotype. A colour somewhere in between green and turquoise, however, these birds do have a much paler mask. Genotypical it is a aqua / turquiose bird. Unfortunately one named these birds apple green. This is confusing and unnecessary because in this manner we stick a separate name to a mutation combination. For this reason many people think that this is a mutation in its own right and that is not the case. Giving a separate name to a mutation combination must be avoided as much as possible. Considering the rules in the international namingsystem we call it AquaTurquoise. (Combinations caused by multiple alleles are named by a ‘ blending’ of both names of the base mutation, e.g. AquaTurquoise. Capital letters are used to indicate the start of the mutation: Aqua and Turquoise) The AquaTurquoise type is not in demand in the BVA (Belgian Lovebird Society) nomenclature because it is a combo, however, it is an excellent bird for breeding turquoise and aqua birds. (top)
This type originated in the USA in the eighties. In this mutation the psittacine in the mask and the tail dots is not red but orange and because of this differs from the wild type. Orange face inherits recessive. (top)
Originated in The Netherlands. In this mutant the psittacin in the mask and tail dots is light orange pink. Pale head inherits as a dominant character. SF birds show much lesser effect than a DF bird. The DF birds are the most wanted for shows. The general body colour verges slightly on aqua. The remaining parts are equal to the wild type. (top)
Alterations in psittacin and eumelanin distribution:
Originated in 1997 in the USA. From a pair dark green / ino x green the first opalines hatched. Most remarkable feature is that the red psittacin of the mask has extended to the back of the head. The general body colour is a somewhat duller green, the rump is almost completely green and the black and blue tail dots have disappeared, and so the red colour prevails in that area. Opaline is a sex-linked character. (top)
Mutations of the feather structure:
The dark factor
This factor causes an alteration of the width of the spongy zone. Another blue colour is produced by interference in this zone and more light is absorbed. The result is a darker coloured bird. The darkfactor is a semi-dominant character. That means that the colour of SF birds is in between the colour of green birds and birds having two dark factors. Green birds with one dark factor are dark green (D green), with two dark factors double dark green.(DD green) (top)
The violet factor
This factor alters the structure of the spongy zone. Because of this alteration blue interference changes into violet interference. This violet colour inherits dominant and can be bred into almost every other mutation, however, it will be best visible in birds coming from the blue series having one dark factor (dark) or birds from the aqua series having one dark factor (double dark). Combinations with other colours might cause confusion and should be avoided. (top)
Manifestation originated by crossing-over:
Originated by crossing-over between cinnamon and ino. In the green series these birds are yellow with a red mask and red eyes, a light blue rump and the flight feathers are light brown. One might think that we have to deal with a fallow type 2 (dun fallow). However, the green suffusion at the lower abdomen lacks, the eye colour is too dark and the inheritance is different. Fallow inherits autosomal recessive and this type inherits sex-linked recessive. The chance on crossing-over between cinnamon and ino is 3%.
The phenotype was first described in Budgerigars. In that species one gets yellow birds with light brown wing markings looking like the pattern of a lace doily. The late Cyril Rogers named these birds “lacewings”.
When the first lacewings arose, one did not know nor understood that it was the result of crossing-over. The cinnamon-ino phenotype in Budgerigars is rather unique with respect to most other species and therefore justifies the name “lacewing” as long as we remember that it is in fact a cinnamon-ino.
It is sometimes a problem that many novice breeders think that they have to deal with a separate mutation. Therefore we soon became aware that for this crossing-over no special names must be attached. What we must do is to make clear what combination this actually is.
The moment we have to deal with a crossing-over, we must write it down as the two mutations involved linked with a hyphen. Both mutations are situated at the same chromosome after crossing-over. Simply “cinnamon-ino” will do. It is easy to remember because it is the same spelling as “crossing-over” which is composed as two words linked with a hyphen. (top)
© Dirk Van den Abeele