Some
history and a little personal experience over the last 40 years breeding them.
© Alan S. Bias
I’ve been keeping and breeding Guppies since I
was eight years old ca. 1969. Prior to
this my father kept a few tanks of near wild-type. Including a tank in front of my high chair as
an infant. Around 1982 my involvement
with the International Fancy Guppy Association (IGFA), along with the breeding
and showing of pedigree Guppies began.
After several years of dabbling around
with various Delta strains in 90 tanks, I became intrigued with the world of
Swordtail Guppies after finding most Deltas just too large, short lived and
sluggish at maturity. More importantly, Delta
demonstrated a general lack of anterior-posterior autosomal color-pattern which
had been selected against in a quest for the long sought after solid-colored Guppy.
I formed a long-lasting friendship with the late Don Sauers, a breeder who
dedicated most of his years in the hobby to promoting and showing the Swordtail
Guppy. Don did not maintain a large
fishroom in his home at the time. Guess
he saw enough fish working in the pet industry. Around 40 tanks in total, if memory serves. Of which, one was a large 80+ gallon homemade
plywood tank painted blue with a glass front.
In which me kept various African Cichlids. Several of the breeding tanks were devoted to
his limited interest in Deltas, while the majority housed his beloved
Doublewords (Ds), Lowerswords (Ls), and a few Topswords (Ts).
On my first visit to his home in the early-mid
1980s in Columbus, Ohio he pointed out the fish he wished to keep and handed me
a net. For the next several years, in conjunction with Fred Roll and
several others, we would show fish against each other one week, and swap stock
the next. Swordtail Guppies have
captivated me ever since with their variety, longevity and hardiness.
In the late 1980's and
early 1990’s it became apparent to some of us breeders the rigid restrictions
imposed upon Swordtail breeders by International Fancy Guppy Association (IFGA)
& International Kuratorium Guppy High-breeding (IKGH)
well defined show standards, as interpreted by
essentially Delta judges, for clear caudal, thin tapering dorsal, narrow caudal
shape, strict body-caudal ratios, and reduced color were not only outdated, but
severely limited potential for the development of new and novel Swordtail phenotypes.
.JPG) |
| Bias Ls ca. 1988 |
Swordtail standards around the world were, and still are for the most part, based on a 1960-70's understanding of genetics and a desire to foster solid colored fish. In the end it limited our understanding of alleles & gene complexes needed to create Swordtails with a free hand as artistic breeders. By doing so, it curtailed improvement in Swordtail color, pattern & shape not only in North America and Europe, but also around the world.
At some point, I decided I am not a “show
breeder”, but a “pedigree livestock breeder”. As a result, I should state that I do
not, have not and will never breed my Swordtails
Guppies strictly in accordance with any fixed set of show standards. I do
not seek to create a breeding show strain within these narrow confines. Rather a sound pedigree domestic strain which
is reproducible over multiple generations.
One that I can in turn regularly show.
My breeding practice is very straight forward
and simple. I keep few records or notes,
and rarely refer to them. Bear in mind,
this applies only to my pedigree breedings and not any planned research
breedings for later publication. I am a
sight-breeder who practices skilled vision.
Skilled Vision has been loosely defined as a learned practice that
allows for recognition and productive results. Based on powers of
observation and acquired knowledge, with far less proficiency in the language
of science. I study genetics not always to make decisions, but to learn
how to avoid reinventing the wheel with every generation.
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| Current Fishroom |
I allow the genotype(s) within my breeding population to lead me in pursuit of the best genetic result for all aspects of fecundity, including color-pattern, by imposing sound breeder selection criteria common to all forms of pedigree livestock breeding. Stated another way, I breed my fish as I once did my pedigree cattle and pedigree sheep, without ever losing sight of wild-type Poecilia reticulata body, shape and form. During this process I select for upper moderate body size and maximum sustainable caudal-dorsal extension in several forms at maturity. All the while maintaining longevity and fertility. I simply show those individuals at maturity, and not before, that fit accordingly into various shows around the world. Which most do with rigid culling and selection practice.
All Guppies, including Swordtails, are comprised
of sex-linked xantho-erythrophore color pigment (if present), over a layer of
violet-blue iridophore structural color, on top of a layer of basal level
melanophores. Under which reside crystalline platelets,
acting as mirrors, which determine reflective qualities based on stacking (parallel
vs. diverse angles).
Variegation (Var) is comprised of collections of
large linear and circular dendritic melanophore in close proximity to violet-blue
iridophores, forming dense structures in body and finnage. Var may be static or motile in nature, i.e.
mood dependent expression. Var is part
of wild-type counter-gradient camouflage, in ectopic fashion (residing in upper
dermal layers). Known in breeder circles
as “Eye-Spots”, they are generally masked by “solid-genotype” found Deltas. Outcross will disrupt masking to reveal Var
in F1 offspring.
All Swordtails, selected for highly reflective
qualities, express Variegation (Var), including Eye Spots to varying
degrees. Highly reflective Swordtails, in
contrast to many or most Delta and several small tail phenotypes, to include Roundtail
& Speartail, are selected against Opaque (Op), i.e. translucent scale. Op, zygosity dependent, results in muted and dull
coloration, in both males and females, by producing diverse angles in crystalline
platelets. OP is an integral part of
wild-type counter-gradient camouflage.
In earlier times, ca. 1970-90, few outcrosses were
made by Swordtail breeders with existing Delta strains, other than neutral IFGA
Green Delta females. Such breedings did
not result in long-term improvement to Swordtail breeding lines. This, a direct result of outcrossing with homogeneous
solid-colored Deltas largely limited to sex-link structural violet-blue
iridophore coloration. In doing so, all or nearly all autosomal
color-pattern could be lost in the short-term. Including reflective qualities.
These breedings simply produced large dead-end hybrids
destined for the show bench, which are genetic dead-ends in a pedigree breeding
program. This occurred only after
several generations of backcross to parental Sword strains to regain sword
shape and extension. Any perceived positive
results in larger size also resulted in corresponding negative results for reduced
reflective qualities, loss of sex-link color, and most
importantly autosomal color-pattern.
Which constitutes the basis for highly reflective qualities found in
Vienna Emerald Green (VEG) Swordtails.
Over the years, I have relied on rigid selection criteria from within my large breeding population to identify and expose unexpressed color-pattern, and limited outcross to near wild-type for infusion of new traits not found in my existing breeding population. Rather than outcross to Delta strains, followed by backcrossing to parental Sword strains.
As a rule, I find Swordtail genotypes to be rather straight forward in mode of inheritance(s) for swords and specific sex-linked color-pattern. Co-expressions and crossover events will often mislead the novice breeder into misinterpreting results. What is often hard for many breeders to comprehend is the concept of sword type, shape, color and extension not always resulting from singular sex-link genes. Often, they are result of unbreakable linked gene complexes. Specific composition can result in better or worse shape and coloration via attraction or repulsion of chromatophores. Such as yellow, comprised of sex-linked xanthophores residing over white leucophores &/or static autosomal Metal Gold (MG) will produce better result than red, comprised of sex-link erythrophores. While blond (b) with reduced size and numbers of melanophores found in Var produces better shape than grey. Refinement tends to come from linebred females, and to a lesser degree males, via positive autosomal concentration. Whereas detrimental result in shape, color and extension tends to arise from negative disruption via outcross.
Swordtail modes of inheritance can generally be described as follows:
Lowersword (Ls) mode of inheritance is traditionally Y-linked for swords and much basic color-pattern, with a neutral "X" for caudal shape and additional male sex-limited color-pattern expression. Periodic crossover to X-Ls is common. Resulting in Lowerswords comprised of Y-Ls, X-Ls and even XY-Ls in co-expression. I should note that stand-alone X-Ls rarely produce show quality results.
.JPG) |
| Lowersword (Y-Ls / X-Ls) |
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| Lowersword (Y-Ls) |
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| Topsword (X-Ts) |
.JPG) |
| Topsword (Y-Ts) |
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| Doublesword (Y-O / X-Ds) |
.JPG) |
| Doublesword (Y-Ls / X-Ds) |
There are several known linked complexes for Ds and color that pass as a single mode of inheritance. To include: Asian X-red, Ds and Asian X-yel, Ds. Both of which can be combined in co-expression with Y-Ls, or Y-Ds, or Y-Ts. Though, best results are often achieved with neutral Y-O males used as sires.
.JPG) |
| Doublesword (Y-Ls / Asian X-red, Ds) |
.JPG) |
| Doublesword (Y-Ls / Asian X-yel, Ds) |
Some Ds are simply true phenotypes. Being solely comprised of Ls and Ts in co-expression, i.e. they are a non-genetic Ds expression.
 |
| Doublesword (Y-Ls / X-Ts) |
Differences in expressions between X- &/or Y-link Ls, Ds, Ts produced by crossover events results in peculiarities that breeders can sometimes recognize with experience and enough breedings. However, most examples of crossover in Ls, Ds, Ts often go unseen by breeders unless regular reciprocal breedings or outcrossing’s are made.
Unfortunately, show standards and the decisions
of the powers to be are not always conducive to the best results in pedigree Swordtail
breeding. How a breeder decides to
select for traits is a personal decision that should be based on long-term
goals, sound practice and ethical considerations for breed attributes. Breed attributes in this case, should adhere
to wild-type Poecilia reticulata body, shape and form. Otherwise, you run the risk of compromising structural
fecundity.
For a pedigree breeding program to succeed long-term
your goals should be generally established well before you make the first breeding. Otherwise, you run the risk of wandering aimlessly. During which time your breeding population
may crash from lack of direction. Yet,
at times you may find need to deviate on occasion to circumvent unforeseen results. That is part of being a pedigree
breeder. Always make as many breedings
as possible and maintain as large a potential breeding population as
possible. In this manner you can make
benefit of Mother Nature’s gift to pedigree breeders. That being the frequent mutations via
segregation and recombination during meiosis that occur each generation. At all times, if and when deleterious alleles
are revealed select against them severely to purge from the
breeding population. Do not routinely
rely on outcrossing to mask them…
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Long-term selection and attention to detail can reward a breeder not only with positive results, but novel phenotypes not yet introduced into Pedigree Guppy breedings. Share them with friends as they can just as quickly disappear...
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