Breeding Guppies - Selective Breeding

There are two main types of fancy guppy breeding regimens and strategies that can be employed in the process of selective breeding. Which one you choose to develop and/or improve a particular strain of fancy guppies should be decided upon once you understand the differences between each discipline.. If you have raised the fancy guppies that you decide to work with from birth, then you will know, as long as you have segregated them properly that you are dealing with a true breeding strain. If you have obtained your breeders through another person, you need to verify that you have been supplied with a true breeding strain of fancy guppies before you invest a lot of time and effort in breeding your fish, in order to avoid a major disappointment. Remember that although female guppies exhibit very few traits that are readily observable on a mature male fancy guppy they do carry the genes for the expression of these traits.

Once you have your tanks set-up for the process that you have chosen to employ, the next thing a fancy guppy breeder needs to do is to select the breeding stock that display the precise characteristics that want to enhance and then use those fish, only, for their project. The characteristics that you may choose to breed for may revolve around an effort to bring out intense colorization  or unique body. patterns. There are also myriad finnage options that you can choose from. Additionally, your quest may be to develop your own strain of fancy guppies. While this goal can be achieved, you should keep in mind that it is an extremely laborious and time consuming process that can oftentimes end in abject failure. Still, for those fancy guppy breeders that are willing to make the necessary investment of blood, sweat and tears, the reward can be very gratifying. In all honesty, though, the main idea in selective breeding fancy guppies is to improve the strain while keeping the true-breeding viability intact. Since few strains are totally pure (producing identical fish from one generation to the next generation), there is a strong likelihood  that you will end up with a new trait popping up in any random drop. New variations can also occur through mutation, as well. These random occurrences give you the opportunity to head down a new path that may be quite different than the one you started out, on. When it comes to the realm of breeding fancy guppies, almost anything is possible.

Line breeding and inbreeding are the two breeding strategies used to produce pure strains of fancy guppies. Initially, you choose a male and female with a number of similar characteristics you find worthy of concentrating on. The proper breeding methods are discussed in another article.

Remember that through the process of superfoetation, it is possible for a female guppy to produce multiple broods through a single act of insemination. Because of this, it is imperative that you make every attempt to properly segregate the males as soon as possible. This will allow you to exercise complete control regarding the selection of the males that you choose to keep your breeding strategy on course as you move forward. It's quite common for male guppies to begin attempting to reproduce in as little as three months time. By sexing your fish as early as possible you will reduce having an inferior male contaminate your breeding stock's gene pool and being responsible for months of work being completely wasted. Attention to detail, as with most things in life, is the name of the game.

As you spend more time observing your fish, your ability to ascertain their sex should improve and result in the amount of time that it takes for you to do so, to steadily decrease. The most dependable way to learn to differentiate the sexes will start by concentrating on the development of the anal fins and their placement in relation to the pelvic fins. The anal fin of a female guppy is posterior to the pelvic fins. As the anal fin of the male guppy develops it will steadily migrate to a position anterior to the pelvic fins and at full maturity will locate itself directly between them.

There is another technique that I have come to use over the years, but I only recommend that you employ it after you have developed a high degree of proficiency in determining the sex of your guppies by more traditional means as outlined above. If you are going to try this technique, I suggest that you try it on a few fish and keep them further segregated until you are able to determine if this method is working well for you. When you are ready to give this is try, use a small, but very high-powered flashlight. While shining the light on a fish, as it reflects the light at a particular angle, a burst of heretofore undeveloped and invisible coloration will be projected off of the body of the fish. Trust me when I tell you that this is not something that is hard to see. It is quite noticeable and extremely foolproof in helping to determine the sex of your guppies at an early age. 

Determining when the female guppy has reached sexual maturity is pretty much a non-issue. Within days of introducing your breeder males to your female tank, it is highly likely that they will be inseminated within hours and within days two things should make it easy for you determine that fresh broods are on the way. First, the part of the abdomen where you are able to see the unfertilized eggs should begin to change colors, shifting from very light to a much darker color. This are of the female guppy's anatomy is referred to as the gravid spot. Be advised that there are exceptions to this darkening coloration expectation due to the fact that some strains of fancy guppies will develop gold, pink or even red gravid spots, especially many of the gold-bodied and albino strains. 

HB Yellow in Early Stage of Fry Development

Czech Gold Red in Mid Stage of Fry Development

German Multi in Late Stage of Fry Development

Photos by Frank Falcone  •  Copyright 2018  •  Do Not Use Without Permission

Regardless of the developing color, the gravid spot will darken to a varying degree and the abdomen will begin to swell as the birth nears. The female guppy has a gestation period of approximately 28 days, but this can be affected by many factors including food and tank set-up, but the most common factor in determining length of gestation is temperature.

Regardless of the type of breeding regimen you choose, be sure to choose one that is commensurate with your tank availability, the amount of effort you are comfortable devoting to your effort and above all else, your level of expertise. You may want to experiment, which is fine, but the more attempts you make at at 'fixing' a particular trait, the more tanks you are going to need. There are pros and cons to the various methods that people use to develop or strengthen a strain of fancy guppies and the more research that you do will help assure your success.

Remember that as you work through the generation of fish produced by your efforts, be on the constant lookout for those males that carry unique characteristics that you may choose to attempt to develop in a new, fixed line of beautiful fancy guppies. I wish you all the best in your efforts.

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