recessive

  • The orange chest mutation in classic colors

    Since we will be discussing the orange breast zebrafinch (PO) in this article, it is certainly interesting to dwell a bit on the history of this mutation first.
    The orange breast mutation (PO) is believed to have originated in Belgium. I consciously write "supposed" because the first orange breast (PO) was actually found at a bird merchant. In Dutch literature in particular, long before the discovery of the first orange breast (PO) in Belgium, zebra finches were described there with characteristics that we can now attribute to orange breast (PO) wearers.
    What we are certain of anyway is that the honor of the discovery of the orange breast (PO) goes to a certain Mr. De C. who in 1978 noticed a rather special gray male in a store. This male had an orange breast bar when normally it should have been black. Mr. DE C. bought this copy, but at the breeding nothing came out of what he had hoped for. At the end of 1978, Paul CH., President of the BZC at that time, acquired this male. There were good and bad surprises with this subject, because unfortunately this male did not live very long. Fortunately Paul CH. had been able to get some young people before. Orange breast (PO) is inherited autosomal recessively compared to the wild form. The orange factor must therefore be doubly present to become visible. He therefore crossed young people between them and quickly took out the first orange breasts (PO).

    Already the first orange breast breeder (PO) made the mistake of not combining and developing the orange breast (PO) with classic colors (gray, brown, pale back, masked) but he rushed directly on the combination of the orange breast with black breast (PN) and other mutations. From that moment on, every orange breast breeder’s dream was born to produce an all-orange zebra finch.
    Due to having burned the breeding stage in the classic colors, the following question remained :

    Are there any specific characteristics that we see in our classic orange breasts, are they just annoying derivatives of the presence of the black breast mutation (PN) or are these specific effects of the orange breast mutation ?

    What do I mean by that? Often the orange chest gray or orange chest brown reveal not well defined cheeks. Likewise, there is often an orange hem on the fenders. Also, the chest frequently flows upwards and the belly shows patterns. All these observed characteristics are quite disturbing.

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  • Zebra finch genetic calculation software

    Small practical software allowing to have the probabilities of the results of a mating according to the mutation (s) of the respective parents. It can be put on USB sticks, no need for an internet connection to use it.

    Before that, we will obviously need to know the genotype of each parent. To help you determine the mutation or combination of mutations to which your zebrafinch belong, you can refer to: Illustrated glossary of mutations in zebrafinch.
    That said, I would say that this application is only an aid. The best thing will always be to understand how each mutation is transmitted. For this, I also advise you to have a good basis to consult the article: Zebrafinch genetics : Instructions.

     

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  • Application of zebrafinch Genetics

    Here is a site, also available in application, dedicated to the calculation of the genetics of zebrafinch. ZebraCalc allows you to have the probabilities of results depending on the mutations of the respective parents.

    Before that, we will obviously need to know the genotype of each parent. To help you determine the mutation or combination of mutations to which your zebrafinch belong, you can refer to: Illustrated glossary of mutations in zebrafinch.
    That said, I would say that this application is only an aid. The best thing will always be to understand how each mutation is transmitted. For this, I also advise you to have a good basis to consult the article: Zebrafinch genetics : Instructions.

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  • Zebrafinch genetics : Instructions

    1. Introduction

    The breeding and competition of zebrafinch has grown considerably over the past fifteen years. In order to improve the size of the new mutations, breeders also have recourse to conventional "split" birds.
    Some manage to combine several mutations. All this made it essential to know a minimum of applied genetics. It is this minimum that I would like to present to novice breeders.
    This is not a complete course in genetics, but a simple presentation of the method I use preceded by some basics.

    2. The zebrafinch and its mutations

    A zebrafinch has a number of visible characters (size, shape, designs, color, sex) that constitute its phenotype. It can have, in addition to other unexpressed traits (it is said to be a split). The set of traits, expressed or not, is called the genotype.

    A young zebrafinch grows out of an egg cell, the result of the fusion of the nucleus of a father's sperm and the nucleus of the female's egg. The bird's genetic program is already there: A series of cell divisions and coded information will (or not) trigger the appearance of the characters. The encoded information is carried by genes located on long filaments contained in the nucleus: chromosomes.
    All chromosomes go in pairs: each chromosome therefore has its counterpart.

    There are two categories of chromosomes :

    - Sex chromosomes :
    • XX in the male
    • XY in the female

    - Autosome chromosomes.

    The gray zebrafinch living in Australia is the source of all of our farmed zebra finches. It has a whole set of genes distributed in its chromosomes.Whenever a new mutation has appeared, there has been a change in an original gene (and it has been shown to be hereditary). The original gene and the mutated gene are located in the same place called a locus on each of the homologous chromosomes.
    Both genes are alleles.

    Genetics of zebrafinch 4

    A bird is pure (homozygous) when all of its alleles carry identical information.
    A bird is heterozygous when at least one pair of alleles carries different information about the same trait.

    We currently know about twenty different mutations of the gray zebrafinch.

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  • Genetic transmission of physical characteristics

    If you ask at a meeting of zebrafinch lovers a question about the genealogy of the masked, the pastel, or a black cheek, you are sure to receive the right answer.
    But if we ask the genealogy question about the format (size), the shape of the head or the length of the beak, the answers will be multiple and different.
    Some will say intermediaries, others dominant, etc.

    Nevertheless, these characteristics follow Laws of Mendel. Many breeders do not believe this explanation, but it is true. It seems that the laws no longer behave in a strict way as for the mutations of colours. A wider variation in the format (size), shape of the head, etc... seems normal.

    Law of independent assortment

    In nature, zebrafinch have the same variation in size. And, in the process of domestication, this difference in variation has increased. Our cultivated zebrafinch are on average two centimetres wider than their ancestors in nature.
    In the articles, we always recommend a hard selection at the level of format and model taking into account the differences between the parts such as the head, the body, etc.

    But the format and the model are driven by genealogy. The body shapes are driven by factors.
    The question that arises is: Is there a relationship between the different factors that govern the format, the model, the shape of the head and the beak ?

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  • How to recognize a male split of black chest mutation

    The aim of this article is not to establish an unstoppable rule for the recognition of a gray male split (carrying) the black breast mutation. Rather, it aims to gather the clues that will allow you to identify it.
    For this, every detail of the mutation is taken over, according to what I observed during the selection of my strain of gray black chest.

    Before starting to analyze each possible clue, it seems important to me to bear in mind that the black chest mutation changes the shape of the drawings. To identify a split of the black chest mutation, I also advise you to take into account all the clues described in this article.

    Let’s proceed and analyze the phenotype of a gray black breast from the head to the rectrices in comparison to a gray split the black breast mutation. To identify each descriptive term used, you can use this diagram : Descriptive terms in zebrafinch.

    1. Mustachial line

    Black chest : The moustachial line will be pronounced and intense black.
    Split (/) Black chest : The moustachial line may be more pronounced than on a gray, however this does not constitute for me a sufficient clue.

    2. Tear line

    Black chest : The tear line disappears (ideally according to the standard) or only a fine line remains.

    Tear line

    Split (/) black chest : Different cases depending on the force of expression of the mutation in the split.

    - The tear line is present and fine :

    tear line is present and fine

    - Tear line is present and wide :

    Tear line is present and wide

    - In some cases, the tear line of a split black chest may also be absent. It will be necessary to rely on the other clues to know if it is a split or a black breast in its own right.

    3. Cheeks

    Black chest : The drawing of the cheeks will extend up and back of the head.

    extension of cheeks black chest extension of cheeks black breast neck

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  • Illustrated glossary of mutations in zebrafinch

    I made this glossary to illustrate in photos the existing mutations in the zebrafinch.
    He can help you identify the mutation (s) of your zebra finches.

    Important precision :To identify the genotype of your zebrafinch, it will be necessary to take into account that a zebra finch can carry a mutation without being mutant.
    Being a carrier (/, split) of a mutation means that it is partially present (genetically speaking). From the visual point of view the partially carried mutation will not be seen or only by some clues present in the appearance of the bird.
    In this case, it will be necessary to have a trained eye to determine the genotype. Sometimes check couplings will be necessary.
    Your zebra finch can also have several mutations, the possible combinations are numerous.

    This glossary is based solely on the phenotype (visual characteristics) and single mutations (not combined).

    Grey (GR)

    The gray zebrafinch is not a mutation, it is the original (wild) type.

    Gris male Gris femelle

    1. Gender-related mutations

    The female can never be a split, so she is either mutant or non-mutant.
    The male can be a split of the mutation.

    Brown (Br)

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