© Alan S. Bias
Permission granted for nonprofit
reproduction or duplication of photos and text with proper credit for learning
purposes only.
November 26, 2012
Panda Male (XYMw PkPk) |
Introduction: As I don’t breed purely
by scientific method, nor solely for show and consider myself a stock breeder
first and foremost, I’ve been searching for a term or phase to encompass this
amalgamation of three distinct schools of thought. One that describes what guppy breeding means
to me and my approach towards it. Recently,
long time Betta breeder and judge, now fellow Swordtail Guppy breeder, Prof. Leo Buss offered up the
following in correspondence: “Pursuing
aesthetic goals in a scientifically informed fashion.” As this is much more eloquently stated than
my abilities allow for, that’s what it shall be.
It is generally accepted the basic Pink Moscow (Pk +
Mw) or Panda phenotype arose in several locations to include Europe and
Asia. The late Japanese breeder Yoshiki
Tsutsui is generally credited for the first documentation and stabilization
into a recognizable strain, which he named “Panda.” The following is not intended to be all
encompassing, and will focus on color / pattern variants and not those
involving finnage: long fin
variants. It is based for the most part
on personal experience and observations of other breeder’s results. To a lesser degree incorporates prior
publications, of which I found to be minimal.
My breeding experience and fascination with Panda’s goes back more than
a decade. In the world of delta guppies
this hardy, fertile and long-lived phenotype often gets little more than a
second glance. Yet, for these same reasons
it maintains a dedicated international following with guppy breeders who also
enjoy active strains…
Breedings: The first Panda strain
I bred in MT was rumored to have been descended from Tsutsui stocks. It had potential for very long dorsal
extension, at least in the world of Panda’s, and periodically produced
homozygous blau pink individuals. In this
mutation the dorsal was always clear.
The caudal expressed as clear narrow flag tails with bits of red and
translucent blue bodies devoid of other color pigment. For this reason I assumed it to be what is
now commonly referred to as European Blau (Eb), which in my mind put some doubt
on the strains origins. This also suggests
the basic Panda phenotype, at least in this strain, was epistatic to red. Barring was only present in a portion of the
males and always partially masked. I did
not attempt to verify if autosomal Z-bar (Ze) or sex-linked Tigrinus (Ti). One of the few outcrosses I did with this
strain involved a Purple Moscow Delta * Panda breeding. The F1 were sib bred to produce a nice line
of Panda with Purple Body Mutation (Pb) with a noticeable reduction of
coloration in pectoral fins.
Two years ago I intended to obtain Panda’s and again
use the homozygous pink (Pk) females joined to select Purple Moscow (Mw) males
as foundation for a new strain. By doing
so would produce a Panda strain for both blue and purple peduncles. But this would have to wait. After obtaining, my current Panda strain
initially demonstrated poor viability in females which necessitated an outcross. Subsequent outcross with Panda males as sires
seemed to confirm weakness in females. With
no available classes for North American show entry, interest and availability
of Panda’s in North America has seriously decreased over the last decade.
Strain
Reconstruction
Generation1: For initial outcross I set up a breeding
group consisting of a grey Panda male with three existing sons to be bred with
several Golden (gg), IFGA Bronze Delta, females obtained from breeder Rick
Grigsby. These females were utilized
only for initial outcross to produce 1st generation F1 and discarded
shortly thereafter. All heterozygous Pk
males in the F1 were discarded. I’ll
note that all F1 males were traditional dark shouldered Moscow Delta phenotype
with a weak snakeskin pattern in the peduncle and dark variegated dorsal / caudal.
R.
Grigsby Bronze Delta Females
|
Generation2:
Resulted from a BC1 backcross, again involving
all four original P sires and a select group of 6 F1 females. In this manner I could reinforce any retained
X-link Moscow color traits and also produce 50% Panda. It had to be considered such a route could reinforce
any remaining detrimental X-linked fertility traits I was trying to eliminate. Heterozygous Pk males and females in the BC1
were discarded. Only those males and females
which expressed homozygous Pk in conjunction with Mw were retained. Staring with this generation females were
selected for increased green iridescence on the topline.
Generation3: Production of the 3rd generation
left me with a bit of a dilemma. The 2nd
generation BC1 in theory had recombined the original X’s in 50% of females and 100%
of males also possessed the same X.
However, with continued backcross it was possible to lose the autosomal
recessive gg. Not only did I wish to
retain this trait into the 3rd generation, but wished it to
express. For this reason I sib bred the 2nd
generation BC1 offspring, and hoped 1st generation simple outcrossed
had resolved issues with females.
Several 2nd generation BC1 males were
individually set up with 2-3 sibling females each. Drops were collected from each breeding group
to identify which, if any, males and females were heterozygous for gg by
production of Golden offspring. After
one male was identified, all other breeding groups and their offspring were
discarded. This decision based on his
superior phenotype and as a means to conserve space
2nd
Generation Heterozygous Golden Panda Male (XYMw PkPk gg)
|
From this sole breeding group it has been possible
to produce strong, hardy and viable Panda with the addition of an autosomal
Golden Pink Moscow Variant. Collection
of fry from this group is ongoing to identify any sons which exhibit superior
phenotype to their sire. In effect, an
intentional genetic bottleneck for specific intent.
Generation4: To date most members of this generation
result from ((Golden Pink Moscow) * (Golden Pink Moscow)) breedings. As expected all are gg and will likely be
maintained as a distinct line. Golden guppies
are known for less density of coloration in the body and finnage. Pk still has the same effect on melanophores
on scale edge, only now more exaggerated not only in body, but especially
finnage combined with gg. Many grey Panda
express partial barring that is near completely masked with maturity. So far this barring is present in 100% of gg
males, but was not expressed by their 2nd generation sire in the photo above . This would seem to suggest either a X-linked
Tigrinus (Ti) or an autosomal dominant version of Zebrinus (Ze). As males of this phenotype near maturity the
barring is still completely visible. The
peduncle has darkened heavily, but retains very iridescent features.
Golden Panda Females (XX PkPk gggg) |
Immature Golden Panda
Males (XYMw PkPk gggg) |
Additional non-Pk females containing genetics for
Pb, blond (bb) and albino (aa) have been introduced for production of other
Panda variants. Sib breedings of F1
offspring have commenced. In each case
of outcross utilizing Panda males the expressed Moscow Phenotype in F1 hybrids remains
surprisingly consistent: 1. Blue
shoulders, 2. Silver snake-skin like peduncle and 3. VAR finnage. This being nearly identical to the earliest
reported Moscow half body snakeskin strains.
Is this indicative of the initial Moscow inputs of the strain or does it
include those from introduced females? I
believe it does reveal the three traits to be in “complex” as little if any
deviation is visible. The most visible
stems from introduction of yellow color pigment via my Vienna LS females to
produce blue-green shoulders, yellow snake pattern and green VAR finnage.
F1 Hybrid (Panda * Albino Vienna LS) |
Discussion: Pink Moscow as they
better known in Europe, are a composite phenotype created by the blending of predominantly
Y-linked Moscow (Mw) and homozygous autosomal Pink (Pk) traits. In a basic grey body form are notated
as: XYMw PkPk and commonly referred to as Panda’s. A quick search of images and breeder webpages
on the internet will reveal subtle variations between individuals, both male
and female in grey form. It will also show variants with additional
autosomes. Are these examples all
reflective of the original phenotype documented in Tsutsui’s Panda strain, and
for that matter what constitutes a strain?
Generally, a named strain is a very line bred or
long-term bred to produce recognizable phenotype. Individual breeder(s) do so in hopes of a
strain which breeds true to itself with a high degree of replication. It takes line breeding to reinforce many of
the subtle traits a strain is known for.
Those that go beyond simple sex linkage or autosomal inheritance
resulting in phenotypes from combination and complex. A hybrid phenotype is just that, it is not a
strain. The IFGA and other show guppy
organizations tend to get around this quandary in a rather simple fashion. They view things almost exclusively based on
categorization by visible phenotype as expressed at the moment, and not strain
names. This works rather well for
judging purposes, in most situations, and avoids a lot of the pitfalls they may
result from differences of opinion on genetics.
Some strains are highly fixed to a single phenotype
with little variation and many breeders adhere to this in both practice and
philosophy. Others may be recognized for
autosomal variations such as grey, blond (IFGA gold), golden (IFGA bronze), or
albino. They may also reflect variations
such as solid or variegated finnage as in snakeskins. Or even short fin or long
fin variants. The list goes on. Again, many breeders adhere to this more
“fluid” definition of a strain in both practice and philosophy, while others do
not. I fall into this latter group of
breeders preferring very complex, yet fluid strains that express a host of
variation. The only true precursor is
you are breeding for intent.
When breeder intent is to duplicate the original
definition and you continue breeding along criteria that will further refine
the results to meet that original definition, you are breeding towards a named
strain. To further argue that source
genetics must be documented as descending from the original breeder is
counterproductive. Simply do so if you
feel a need. Most guppy phenotypes are
readily reconstructed from unrelated sources.
What is important is your understanding of them. Each of the variants presented either in
discussion and/or photographs in this article are genetically Pink Moscow’s. So to answer the initial question: Are these examples all reflective of the
original phenotype documented in Tsutsui’s Panda strain? No…
As a breeder you have the discretion to put your own
individual signature on a strain through modification. I find
it best to acknowledge any deviation and resulting variants. In example, my primary interest in guppy
breeding has always been and will likely always be Swordtails. In specific Vienna Emerald Lower
Swordtails. My strain is comprised of
several lines composing many phenotypical traits that result from specific
combinations of X, Y or even X & Y-link traits further influenced by
several autosomal traits. These traits
may be standalone or they may be in linked complex. I acknowledge they do not meet the original documented
European definition of a Vienna Emerald, for this reason I refer to my
swordtails as of “Vienna Type” and not “Vienna Emerald”. In documenting I normally refer to specific
variants by genetic name and notation.
Example: Asian Blau Vienna Lower
Sword YLs SmIr X Ab.
3
month old Golden Pink Moscow Males (XYMw PkPk gggg)
|
As demonstrated in my recent breedings, with a
little knowledge of guppy genetics and patience a breeder can often easily
reconstruct phenotypes, including the Panda from a single male in as little as
two generations. The inheritance of the
Pink trait is no different from many autosomal recessive alleles. Either sex is capable of passing Pk in
unexpressed heterozygous form. Still it is best to qualify use of the
term “unexpressed”, as some visible modifications to melanophores in
heterozygotes are visible in both Pk and gg.
Visually Pk shares several similarities with Golden (gg), also known as
IFGA Bronze, in relation to melanophores.
Homozygous Pink Moscow fry, regardless of additional
autosomes, are easily distinguished at birth by a highly visible float and eyes
which seems to fade with age. Panda are
found to have either black or silver eyes at birth. With the appearance of secondary coloration
from Moscow traits over the eye socket dominant or flashing males take on a
nearly pure black eye. Careful
examination of fry under handheld magnification reveals
a dark region over the topline extending to and increasing in coverage
over the cranial region and above the eyes.
This stems from enhanced manipulation of melanophores in these areas and
to a lesser degree in the flanks above the abdominal cavity. This continues to increase with age and will
lesson perceived brightness in regions found at birth.
Grey
Panda Females (XX PkPk)
|
Just the opposite seems to occur in the lower
peduncle, with an increasing reduction from below the dorsal base towards the
caudal base. Further revealing an “opaqueness”
of flesh that is found over the entire body in Pk homozygotes. Again,
a similar phenotype found in homozygotes for both Pk and gg phenotypes.
Without the addition of the Half Black genes
Nigrocaudatus (Ni or NiII) to Pk it is
hard to see the gene pink as “color pink”, as it more resembles “white”. Pink guppies are considered capable of
expressing all colors typically found in guppies except red, as a result of the
Pk gene. It should be noted the
existence of several Pingu strains w/visible red Mw in the shoulders. This and the ability of Panda to express Pb
in the peduncle and Homozygous Eb Pink
Moscow to express limited red in the peduncle casts some doubt on the theory of
homozygous pink completely suppressing expression of red pigment via
epistasis. When Pink is found in combination
with the Ni or NiII red color pigment in finnage is modified to a pale orange. Fixed strains in this combination are often
referred to as Pingu. In some instances
it is difficult to tell the difference between this modified orange and
unmodified yellow pigment. Red pigment
may result in clear or light dorsals, while yellow can enhance.
Grey
Bodied Heterozygous Golden Pink Panda Female (XX PkPk gg)
|
Panda are not a round tail guppy in a traditional
sense as a result of genotype. Caudal
shape is a result of homozygous Pink modification through suppression of
Pigmentierte Caudalis (Cp), but may be further enhanced if X &/or Y-link round tail (Rndt)
genetics are present. Most breeders find
it wise to select for the darkest caudal and dorsal with clean round shape to
avoid either exaggerated clear trailing edges, clear patches, or irregular
shape.
Homozygous
Pk Vienna Swordtails - Photo Courtesy of
Björn Lundmark
|
It is routinely assumed by many breeders that homozygous
Pk in conjunction with Mw modifies parental strain finnage (dorsal and caudal). This assumption is twofold in error; 1. Extension genetics are not removed, just suppressed
to varying degrees by epistasis. 2. Homozygous
Pk in itself is capable of suppressing extension genetics in several strains. In example above are Homozygous Pk Vienna
Swordtails bred by Björn Lundmark.
In recent years I have noted several autosomal homozygotes
routinely result in body modifications.
In well-bred Panda strains both males and females exhibit a type of
“chunkiness”. Being defined as; more tightly coupled in both the abdomen and
peduncle than either parental stock.
Overall structure of the head and gill plates are also more “rounded”
than either parental strain. Though
expression may be enhanced from combination of Mw + PkPk, there is a similar
effect found in homozygous AbAb fish. An
autosomal recessive Zebrinus (Ze) in homozygous form has had just the opposite
effect in my Vienna LS; 1. Delaying maturity to produce a “long lanky” body. 2. Diminishing
dominant epistatic effect of Y-link LS over X-link DS to reveal “topspikes.”
Panda
Male with X-link yellow pigment (XYYMw PkPk)
showing clear edge on caudal
|
One of the more noticeable traits in Panda is prevalence
for clear trailing edge on caudals. As
dorsals commonly exhibit less of this modification it would be easy to believe
the effects of pink are limited to the body and caudal coloration. Or are they?
Panda caudal and dorsal color is biased towards blue iridophore and
melanophore modification. While the
dorsal in a Panda often looks very dark and solid, outcross often reveals Variegation
(VAR) to be present. This is a noticeable
deviation from expressions held in common with gg. Homozygous pink is likely suppressing
expression of VAR, while it is commonly expressed in gg. Depending
upon mood dorsals can be very lightly colored in Pink Moscow. This may result if red pigment is suppressed
by Pink or if color is predominantly based on blue iridophores. Incorporating an X-link for yellow fin
coloration can override some of these issues.
Without any additional color pigment and reduced
melanophores Blond Panda often express clear dorsals and are rather flat in
body color. Blond Glass Belly Panda with
reduced iridophores even further exacerbate this expression. While Albino Panda can be similar to blonds
in expression, there are marked differences in both iridophore and melanophore
expression. Not so “washed out” comes to
mind. Male and female grey Glass Belly
Panda, with higher retention of melanophores, clearly show reduction of
iridophores in both the body and finnage.
Glass
Belly Panda (XYMw PkPk GbGb ) courtesy of P Shaddock
|
The overall body color on Panda is a result of blue
iridophores in combination with homozygous pink. It is easily modified to purple with the
addition of Pb or green with the addition of yellow pigment. While a Panda may seem black, closer
inspection reveals standalone blue is still visible in select areas on the skull,
shoulders, peduncle and caudal base. Most
breeders select for a solid black coverage with attention to degree of
iridescence. A flatter black Panda has
been achieved by European breeders, and appears periodically in my stocks,
similar to a Black Moscow Delta counterpart.
From available evidence it appears this was accomplished with increased silver
iridophores at the expense of blue.
Grey
Panda with pronounced silver iridophores
|
All finnage on a basic Grey Pink Moscow expresses
nearly solid black, regardless of additional pigment, though iridophores can
bleed heavily into the caudal base. This
includes; dorsal, caudal, pectoral, pelvic, and anal. Homozygous Pk results in intensified
collection of black melanophores in certain regions of the body and fins. At first glance the addition of homozygous gg
to homozygous Pk appears to reduce this effect; Magnification reveals it to be further
amplification of collected melanophores in limited regions.
5
month old Golden Pink Moscow Males (XYMw PkPk gggg)
|
One of the more genetically intriguing variants combines
both Pingu and Panda phenotypes: (XNi
YMw PkPk). The
anterior still resembles Panda. There is
deviation from Panda phenotype in all finnage.
Not just limited to the typical lighter colored Pingu caudal and dorsal. It includes the pectoral, anal and ventral
fins, which have lost all or most black coloration as the result of Ni. (Note: Reasons will be expanded upon
further down.)
Pingu
Panda (XNi YMw PkPk) courtesy of D Czajkowski
|
The posterior is classic Pingu peduncle and finnage,
though pink stops just short of early versions which extended to dorsal
base. Many Pingu today are similar and
exhibit black on the topline in front of the dorsal with a Mw shoulder, likely
from Moscow Delta foundation sires.
Original Pingu had two distinct shoulder types. One was darker in shoulder and topline, but
did not possess Mw genotype. The second
was an “Old Fashioned” shoulder pattern in which a red stripe was suppressed
via epistatic effect of Pk. Leaving for
the most part only white leucophores or silver iridophores visible (see photo below.) In both cases Pk often
extended into the abdomen.
Ca.
1985 Pingu (XNi Y PkPk).
Descendants of David Liebman stocks
maintained by late Don Sauers and myself
|
Pink
Moscow Variant coloration at the juncture of peduncle / caudal (not
inclusive of all potential)
Conclusions:
Pink Moscow are
routinely bred and shown in both Asia and Europe by a dedicated following. A lack of defined class in North America
has restricted both interest and development. In all locations a loose
definition of what actually comprises a Panda Guppy has allowed for a diversity
of type to arise from a singular phenotype.
Based on the ease of creation it would be safe to
ascertain that few if any Pink Moscow found today actually descend from either
initial European or Asian (Y. Tsutsui) stocks.
The diversity of phenotype in today’s Panda strains not only is
indicative of a variation in foundation Moscow genetics utilized for Y-link
traits, but also female genotype.
Many guppy breeders view the Panda phenotype as a
simple combination of Moscow blue and homozygous Pink. This fails to encompass:
1. Additional
autosomes breeders can incorporate to create complex phenotypes very diverse
from original descriptions,
2. Neglects
the line breeding needed for refinement into individual Strains,
3. The
diversity of genetic sources used in foundation lines,
4. Degrees
of intensity based on mood of the individual fish,
5. A non-demanding physical structure.
Basic Panda are fairly similar in genotype. After initial crossing of parental stock,
differences can be readily visible for several generations depending upon
breeder selection, compounded by loss or retention of any X-link Moscow traits. There is clear evidence of manipulation of
black melanophores at birth in Pink Moscow’s.
As with most guppy strains a clear progression of secondary
color / pattern development commences at onset of sexual maturity. Increased iridophores to reveal silver / blue
and expression of barring; followed by appearance of color pigment; and finally,
in contrast to cellular layering, further enhancement of black melanophores to
partially overshadow iridophores. Suggesting
some black in Panda’s is ectopic in nature and not limited to lower cellular
levels.
Panda
Moscow Lower Sword (LS
+ Mw + Pk + Ssb),
Photo
courtesy of breeder Olof “Ollie” Boberg
|
In all but a few Pink Moscow strains coloration is
highly motile in nature as a result of Mw gene(s) interaction between black
melanophores in conjunction with structural iridophores & color pigment. When possible it is wise to delay selection
of your breeders to identify those with best density / intensity of coverage in
body and fins. As a result of foundation
Moscow Blue (blue iridophore) genotype, descendants of Tsutsui Panda stocks
were very dark colored in the peduncle.
There may have been a blau component (Eb or Ab) which was not
documented. Today, depending upon
breeding Panda are also found in both green and purple body mutation (Pb). This could stem from use of Pb females or
Purple Moscow males as parental stock instead of Blue Moscow.
Observation reveals to breeders how zones of
regulation are allowing for the varied appearance in today’s Panda. Easily evident are increased melanophores in
topline and finnage, iridophore / pigment modifications anterior and posterior. Less noticeable at first glance are zonal effects
on patterns such as Zebrinus / Tigrinus and Snakeskin. Normally found over the entire peduncle, like
many other strains, they can be restricted to either upper or lower quadrants
in Pink Moscow. In the males below barring
is present in both upper and lower, while snakeskin is restricted to the
upper. I have not witnessed the latter
in inverse, snake in the lower, as is possible with other traits such as
Saddleback (Ht).
(Left photo) Panda
Moscow w/barring in upper & lower peduncle. Snakeskin in the upper peduncle. |
(Right
photo) Blond Vienna LS w/barring
in upper peduncle quadrant
|
Homozygous Pink has often been characterized as
having its greatest effect on iridophores.
However, this is not necessarily the case. Pk exerts a far reaching impact on all levels
of cellular structure in regards to color and pattern. Most breeders acknowledge guppy color cell
layering to consist of: A lower layer of
melanophores (black); a middle layer of leucophores/iridophores (minimally
being blue / silver / white); a top layer of zantho/erythrophores (yellow /
red).
In Goodrich, et al., (1944) regulation of phenotypic
expression of melanophores by autosomals Blond and Golden are studied. He describes Wild-type as “in some respects
intermediate between the Golden and Blond.”
His research divulges several
types of melanophores: 1. Dendritic (on the scales), 2. Corolla and Punctate (on the body). For the most part they are present prebirth,
at birth or shortly after birth. While
Wild-type and gg guppies have the largest dendritic melanophores, bb has the
smallest. Yet wild-type and bb have nearly the same amount (concentration) per
square mm of tissue sample.
Goodrich,
et al., (1944)
|
In Nayudu, et al., (1979 No. 2) melanophores in
Wild-type and three other sex-linked traits are studied. Of particular interest in relation to Pk are
her results for Half Black (NiII). She
defines them as “mutant”, being ectopic and larger than normal. The mutant melanophores of NiII, Flavus (Fla)
and Cp are present in at least the posterior peduncle region, caudal / peduncle
juncture and dorsal base.
Nayudu,
et al., (1979 No. 2)
|
Autosomals blond and golden are both considered
epistatic to black in homozygous form.
Not by directly affecting melanin synthesis, but by regulating
melanophore size. Blond has little or no
effect on Half Black (NiII), which has been shown to consist of larger sex-linked
mutant black melanophores. In contrast autosomal
Pink aggregates concentration of regular melanophores and suppresses mutant
melanophores, based on Panda and Pingu phenotypes. Thus, being in divergence from gg and bb, Pk appears
to regulate in both instances…
Pink
Moscow Male – top (XYMw PkPk)
Golden Pink Moscow Male - center (XYMw PkPk gggg)
Het. Golden Pink Moscow female - bottom (XX PkPk gg)
|
I used to worry that this wonderful little phenotype
would disappear from the scene like so many others have in the past. Yet, the simplicity of genotype allows for
quick reconstruction from many sources.
While the more obvious phenotypes have already been produced in multiple
locals, it’s hard to tell what may be presented by breeders in the future.
On a last note, it should be mentioned that Panda Moscow
are a notoriously slow growing, but long lived strain. After a quick growth spurt the first month it
takes considerable time to reach mature size and coloration. If you have an exceptional bodied male in
with a group of siblings that just never seems to color up to expectations, remove
him to another setting. Often this is
all it takes to reveal the full potential as a result of the motile nature of color
found in Pink Moscow.
The final words in this article belong not to
myself, but the individual who bred, named and documented the Panda strain. In his words:
My answer may be abstract Japanese
way... I first draw the exact image in my mind the guppy I want to create, then
print it in my mind. Then keep thinking of the image everyday when I feed my
fish. After a while, fish start to lead me on what to do and my eyes become
more keen, so often find the guppies I need from my fishroom without adopting
guppies from somewhere else. This is
what I call "Guppy Alchemy." ~
Yoshiki Tsutsui ca. 2005
References:
1.
Robert Gall, (2005), Guppy Labs
e-Bulletin, Base Body Color Pink, Volume 7, (July 2005), http://guppylabs.info/july2005/robert.htm
(no longer active site - wayback machine capture 2012)
2.
Telephone Interview by Tomoko
Young, (2005), A convsersation with Yoskiki Tsutsui, Guppy Labs e-Bulletin,
Volume 5, (January 2005), http://guppylabs.info/january2005/YoshikiTsutsui.htm
(no longer active - wayback machine capture 2012)
3.
Shaddock, Phillip (2010). Guppy Color Strains. Printed in Canada, Pocket Cine Books. [General
Reference; Moscows pgs.: 15-36 / Pinks
and Pingus pgs.: 113-120]
4.
Heike Savelsbergh, Guppyheike
(webpage), Moskauer Rundschwanz, http://www.guppyheike.de/guppys/pink-mosi-rs/ (10.31.12 active)
5.
Winge, O.,
Genetic Laboratory of the Royal Veterinary and Agricultural College,
Copenhaen (1927). "THE LOCATION OF EIGTHEEN GENES IN
LEBISTES RETICULATUS" [gene tables and descriptions]
6.
Petrescu-Mag I. V., et al., (2007(,
Interallelic interaction between the autosomal Blond and the sex-linked Nigrocaudatus gene in the guppy (Poecilia reticulata). AIR 2(1).
7.
Kirpichnikov, V. translated by G.G.
Gause., 1981, Genetic Bases of Fish Selection.
Berlin / NY, Springer Verlag (1981) [gene tables and descriptions]
8.
Shaddock P.,(2008), Blond: a
regulatory gene in the guppy (Poecilia
reticulata Peters 1859). AACL Bioflux.
1(2):161-164. Printed version:
ISSN 1844-8143
9.
Nayudu
P.L., et al., (1979 No. 1), Genetic Studies of Melanic Color Patterns and
Atypical Sex Determination in the Guppy, Poecilia reticulata, Copeia 1979, pp. 230-231,
10. Nayudu P.L., et al., (1979 No. 2), Cytological
Aspects and Differential Response to Melatonin of Melanophore Based Color
Mutants in the Guppy, Poecilia reticulata, Copeia 1979, pp. 240-242.
11. Goodrich H. B., et
al., (1944), The cellular expression and genetics of two new genes in Lebistes reticulatus. Genetics
29(6):584–592.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Breeders of many fish species
are intent on maintenance and preservation of what already exists. Guppies present a unique set of challenges if
only by diversity of genotype. As
breeders it is easy to believe we can add to the equation while forcing them
into a specific mold. An old
adage in the pedigree livestock world states, “You start with a 100% package
and you end with a 100% package.”
All we can do as breeders is re-shuffle the
deck for gains in one area and corresponding losses in another. This is a constant when breeding any species. There is no way around it. Seek a balance in your efforts in conjunction
with your goals to reveal what Mother Nature will allow within your particular environment…
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~