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Ringneck Colour Genetics
8. The Recessive Mutations
Clearhead Fallow
T
his mutation appeared in the mid-eighties in
Europe, and the first specimens arrived in
S.A. in the late eighties. At the time it was
called Buttercup due to the glorious golden head of
the sexually mature cock.
Of the different yellow-headed types, this one
possesses the deepest, most richly coloured
golden-yellow head, to me much more stunning
than the Cleartails. A pitch black neck ring rounds
the rich golden-yellow colour off perfectly. Then the
large dark-red eye with translucent iris, an evenly
diluted plumage overall and light feet and nails
makes this a delightful serene blend of soft colours,
soothing to the eye.
The Clearhead fallow mutation was initially a difficult
mutation to establish, due to various problems
related to breeding. Infertility, a seeming unwillingness or inability on the part of the cocks to mate, or
doing so ineffectively, a high ratio of dead-in-shell,
small eggs and unreliable incubation by the hen
were all situations encountered. Possible explana-
Grey Turquoise Clearhead Fallow
source unknown
tions for the association of this mutation with a poor
reproductive record are discussed in the chapter on
Gene Action. Fortunately, this mutation has shed
those problems by being bred out to strong wildcoloureds, becoming stronger. Today it is a wellestablished mutation and the initial breeding
problems long forgotten, and various combination
colours containing this beautiful mutation exists.
Nestlings are born with dark red eyes, immediately
visible after hatching. They have light feet and nails.
The dilution in plumage is evident upon feathering
and both genders have a lighter head. It is evident
that the iris is translucent in all juveniles, and stays
so. I have noticed in Violet TurquoiseBlue Clearhead
Fallow juveniles a clearer head with a violet hint of a
neck-ring. The cock's moment of glory arrives with
the adult moult and he gets a glorious golden
buttercup head, abruptly cut off with a pitch black
and pink neck-ring.
Its' clear head sets it apart from Fallows in other
species, but we accept that this striking colour
phenomenon is a unique Ringneck characteristic.
Like with the other fallow types, the appearance of
the yellow head, leaving the neck-ring unaffected,
must be related to metabolic
events after the advent of
sexual maturity and the increase in circulating male
sexual steroids that bind to
specific receptors, obviously in
skin cells that switch melanin
production off.
TurquoiseBlue Clearhead Fallow
Louis Bothma
While the a-locus is considered a major one for multiple
fallow alleles, Clearhead
fallow has been paired to
bronze fallow, NSL Ino, and
Cleartail, but no evidence of
allelic relationship could be
found for either of them. It had
been combined with Cleartails
by various breeders in S.A.,
and only green offspring were
produced. Thus far, this mutation is a standalone, is not
allelic to any other mutation
and has its own locus.
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Ringneck Colour Genetics
8. The Recessive Mutations
For some reason the Clearhead Fallow never
attained the popularity of the Cleartail, probably due
to its' early breeding problems and the mass
hysteria that the cleartailed mutation generated. But
in recent years and with the satiation of the markets
A Violet Turquoise Clearhead Fallow going through its 2 year
moult 2013, above & right. Deon Smith
An adult Cobalt Turquoise Clearhead Fallow. Tienie Carr
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world-wide with Cleartails, the Clearhead Fallow is
assuming its rightful place in Ringneck aviculture. It
has a major advantage; its golden yellow head and
strongly-contrasting pitch-black neck ring. How will
combinations with Opaline look like, and Emerald?
Ringneck Colour Genetics
8. The Recessive Mutations
without it. I remember the frenzy very well when it
was made available on auctions in S.A. in the midnineties, the emotions aroused and reckless prices
being paid for it, all the while completely overshadowing another refreshing new mutation,
Buttercup as it was known at the time. It has
probably been combined with every conceivable
mutation, and combinations with other rare or
popular mutations remain the ultimate objective of
many idealistic breeders, at least in S.A. and
probably many other countries where the new
mutations that have appeared are rare or unobtainable.
Cleartail
Nestlings are born with dark red eyes but with light
feet and nails, while some has dark nails. As they
fledge, a lighter head with an iridescent blue neckring becomes evident in both genders. The belly has
Violet Turq Cleartail Stefan Adam
Cleartail is for many one of the most desirable colour
mutations and its beauty continues to fascinate
breeders and fanciers alike. This mutation came to
the Netherlands in the middle eighties from India,
about the same time as the Clearhead Fallow. Its
genetic placement was mysterious with apparently
no matching mutation in other avian species, and it
appeared to represent a unique Ringneck mutation.
Neonates have a dark red eye; the 3rd fallow
requirement; Cleartail is a fallow type. The appeal
of this mutation is no doubt based on its exquisite
harmony of colours, pleasing to the eye, where the
green plumage is brightened, almost luminescent.
The accepted name for it is Cleartail, but South
African breeders continues to use the term
Clearhead Cleartail freely, as they feel the name
Cleartail disregards its most obvious and suave
feature.
This is arguably the most popular Ringneck
mutation ever; I doubt if there are any collections
A juvenile Violet Cleartail. Stefan Adam
a smooth transition to clearness and the tail feathers
are brilliantly clear, but may vary to body-coloured
central tail feathers. A marked brightness of the
psittacin colours is evident. While the hens have a
blue neck-ring, juvenile cocks in their first months
develop a white and light grey neck-ring. With the
adult moult, the cock gets a golden-yellow head. Its
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Ringneck Colour Genetics
8. The Recessive Mutations
neck-ring is bright pink and the melanin ring ranges
from light grey to black. The hen retains the lighter
head and blue neck-ring.
Australia and Germany. Jay from Krameri Aviaries
writes in a blog16: “Cleartail lines all over the world
are known to contain NSL Ino”.
The appearance of a clear head in sexually mature
cocks points toward a metabolic intervention
involving male sexual steroids and its receptor sites
on certain cells. How melanin production in the head
region suddenly shuts down after puberty is not
clear but is probably based on a switching on /
switching off mechanism, where testosterone which
is now present in sufficient quantities, binds to its
receptors in the skin cells of the head region, which
has been switched on, causing a chemical change
inside the cell. The psittacin pigments increase and
boldly brightens up. This feature suggests pleiotropy.
But even worse, the first Cleartails that made their
entry into S.A. and probably elsewhere, was
contaminated with SL Ino as well. Imagine the
situation in those early days, when a Ringneck with
a price tag of a Hyacinth Macaw, produced Ino
offspring. Big money was at stake and many
friendships had a stormy and bitter death, and all
due to factors beyond control. Later imports from the
Netherlands proved to be exactly the same. Confusing breeding results in Ino offspring appeared, as
in some cases, 25% Ino hens were produced in
keeping with expectations from a sex-linked split
male, as well as from two autosomal recessive split
birds. When an Ino cock was bred, it would have
been proof of it being NSL Ino. But those babies
were seldom sexed, as it was believed to be hens
and most were probably culled.
But there were unforeseen baggage that came
along. Babu Chauhan of the UK tells that the early
Cleartails in the Netherlands were interbred with
NSL Ino, as the first Cleartail arriving in Holland from
India was tied up in a breeding pair with a NSL Ino.
This resulted in a substantial number of NSL Ino's
bred from Cleartails, proven in at least S.A.,
Added to this is the possibility that Cleartail may be
another allele of the NSL Ino locus (a-locus), which
has already proven itself as a multi-allelic locus. This
view probably originated from
the close association of the
original Cleartails in Europe
with NSL Ino, a fact that was
not known in those days; all
breeders saw was the appearance of Lutino's from it.
Mauve Cleartail & Violet Turq Mauve Cleartail. Stefan Adam
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This could explain the two
neckring types seen in Cleartails, one darker brown and
the other notably lighter, associated with a parallel different
overall colour tone. Could the
lighter one represents a
(Cleartail)(NSL Ino) combination or heteroallelic? (Heteroallele is the combination in
one individual of two different
allele of the same locus, just
like in PallidIno). And the
darker type a Cleartail homoallelic form
(Cleartail)(Cleartail)?
Ringneck Colour Genetics
8. The Recessive Mutations
Limited breeding results from pairing of a Bronze
FallowNSL Ino X Cleartail, by Wynand Bezuidenhout in S.A. however did not give intermediary
phenotypes but rather wild-coloureds. If allelic, each
one of the brood should have been an intermediary
phenotype and not double splits at all. This is strong
evidence against an allelic relationship and virtually
excludes it. We still do not have an answer for the
two phenotypes, and must consider the lighter form
to be an intermediary form, but with what? Or more
probable, a Cleartail NSL Ino combination: an
individual with paired Cleartail alleles (genes) and
paired NSL Ino alleles, as they are unrelated
mutations? But there are probably many visual dark
Cleartail split NSL Ino's around, so that light Cleartail
morphotypes (appearance types) might be bred
from it, and vice versa.
It is fact that many breeders world-wide have
interbred Cleartails with Clearheaded Fallows, and
unsuspected breeders received Cleartails that were
split for Clearhead fallow. We can expect that
Cleartail Clearhead Fallows exist, which may
account for the darker morphotype.
In the end, given the history of the origins of these
mutations, the unknown blending of different
mutations in specimens acquired and its
widespread prevalence, there could be a complex of
different recessive mutations combined in the
genotypes and phenotypes we see in our aviaries,
with Cleartail, NSL Ino, Clearhead fallow and even
Bronze fallow taking part; it may be hard to find a
pure Cleartail at all. It will probably take years to
unravel the exact genotype of what we see in our
aviaries, as somebody must outbreed any possible
combination type to each of these contenders.
Additionally, the ever-present possibility of modifier
genes and Transcription Factors that may alter the
final colour expression has to be heeded. These
topics are covered in the chapter on Gene Operation
& Molecular Biology.
A group of German breeders are researching the
issues related to the different Cleartail morphotypes.
Breeders of the two morphs are encouraged to
contact Stefan Adam.
In S.A. are Cleartails with clear flights, “Clearwing
Cleartail”. I could study one specific type in the
NSL Ino Cleartail cock
Tienie Carr
aviaries of Kiepie Herholdt in Bloemfontein a few
years ago; it was bred from his imported line of
green Cleartails. The asymmetrical clear flight
feathers on both sides point toward a pied type that
was combined with Cleartail. It is probably a
combination type of two autosomal recessive
mutations, combined through selective breeding;
the answer would have become clear through
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Ringneck Colour Genetics
8. The Recessive Mutations
following breeding data. In his
collection he also had a Blue
Pied with the same pied
pattern of the flight feathers; it
is seen on the photos. But a
peculiarity with this morph is
the delayed appearance of the
clear flights until the adult
moult; it appears together with
the yellow head. Is this a
progressive form of pied, or is
it linked to sexual steroid
activation of receptors? The
blue type unfortunately died
prematurely.
The Dunn Fallow
There is however another
mutation type with the same
name that was established in
Johan Goessens of Belgium's
aviaries; specimens with clear heads, tails and
flights though the latter have a faint brownish tinge.
He wrote he obtained it from another Belgian
breeder more than 20 years before and he bred the
first specimens out of double splits. Initially he bred
Lutino's (no doubt NSL Ino's – gms) and Fallows in
the same nest.
There are two morphotypes; a light and a dark
series. The light series are born yellow and the
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green colour on the neck and the body appears after
one year while the dark series is much darker and
are born with the green in the neck and on the back.
Could this after all be a combo type: a NSL
InoBronze Fallow heteroallelic combination
combined with homozygotic or df Cleartail and that
the two series reflects on a NSL InoBronze Fallow
heteroallelic combination in the light type and
Bronze FallowBronze Fallow homoalleles in the
dark type.