Dachshund Colours and breeding
It's scientific in nature, it's interesting though and for any breeder it is something that needs to be considered seriously, a responsible breeder that it is.
Nellie is Chocolate and Tan, her mother is Red and her father is Chocolate and Tan Dapple. In choosing a stud dog not only does the breeder need to consider the COI - Inbreeding Co-efficiency but also the colouring and pattern.
The breed council for Dachshunds coat and colour publication is a great resource and has been my reference point.
So to start with some of the sciency stuff..
Dogs have 39 pairs of chromosomes.
Chromosomes are long chains of genes.
Genes control the coat colour and coat type.
A gamete is a sex cell i.e. sperm and eggs. Chromosomes are contained inside the cell's nucleus. These are long threads of DNA, which are made up of many genes.
A gene is a small section of DNA on a chromosome, that code for a particular sequence of amino acids, to make a specific protein. It is the unit of heredity, and may be copied and passed on to the next generation.
Some characteristics are controlled by a single gene, such as fur in animals and red-green colour blindness in humans. Each gene might have different forms, and these are called alleles.
Chromosomes are found in the nucleus of a body cell in pairs. One chromosome is inherited from the mother and one is inherited from the father. The chromosome in each pair carries the same gene in the same location. These genes could be the same, or different versions.
Alleles may be either dominant or recessive:
A dominant allele is always expressed, even if one copy is present. Dominant alleles are represented by a capital letter, for example, A.
A recessive allele is only expressed if the individual has two copies and does not have the dominant allele of that gene. Recessive alleles are represented by a lower case letter, for example, a.
Coat types in Dachshunds
- Wire
- Smooth
- Long
Dachshunds in the UK normally have two copies of their own coat type gene.
- Wire - WW
- Smooth - SS
- Long - LL
Wire is dominant to all other coat types and if a dog has even just one W gene it will be a wire, if it has one if the other coat type genes it can pass that gene on to its progeny and produce 'recessive smooths' or 'recessive longs'.
Progeny = a descendant, an offspring
Recessive = relating to or denoting heritable characteristics controlled by genes which are expressed in offspring only when inherited from both parents.
Smooth is dominant to long. If a dog has one S and one L gene it will be a smooth, but it carries the Long gene and therefore can pass it on to its progeny and produce 'recessive longs'.
Long is recessive to both wire and smooth therefore if the dog has a long haired coat it has to have two copies of the long haired gene (LL), two long haired parents can only produce long haired puppies.
Recessives
If a recessive smooth or long is produced in a litter it will only have the coat type genes for that coat type.
e.g. 2 wire parents produce a smooth. Both parents must have one wire gene and one smooth gene (WS and WS).
(From the male) - When the sperm are produced each one either gets a W or S gene.
(From the female) - When the egg is produced each one wither gets a W or S gene.
At fertilisation one sperm and one egg join together, if a sperm with an S gene and an egg with an S gene join together then the puppy will be smooth. The Punnett square diagram below demonstrates this.
The Punnett square is a square diagram that is used to predict the genotypes of a particular cross or breeding experiment. It is named after Reginald C. Punnett, who devised the approach. The diagram is used by biologists to determine the probability of an offspring having a particular genotype.
| Genes in gametes | Sperm W | Sperm S | ||
| Egg W | WW | WS | ||
| Egg S | WS | SS |
Coat colour vs Pattern
Colour refers to the basic coat colour and all dachshunds are one of these basic coat colours.
- Red
- Cream
- Black and Tan
- Black and Cream
- Chocolate and Tan
- Chocolate and Cream
Pattern refers to:-
- Dapple
- Brindle
- Sable
- Piebald
Dominant and Recessive colours
Dachshunds have at least 7 different pairs of genes that control their coat colour. Scientifically genes are identified by letters. The dominant gene by a capital letter and the recessive gene by a lower case letter.
Genes can exist in more than one form called Alleles and depending on what Alleles your dog inherits from its parents will depend on what colour it is.
Black and Tan and Chocolate and Tan
Black and Chocolate are controlled by one pair of genes, this pair of genes is recessive to Red and therefore is both parents are Black and Tan or Chocolate and Tan they cannot produce a red puppy unless both parents have the "e red gene".
Black and Tan dogs are BB.
Black and Tan dogs carrying chocolate are Bb.
Chocolate and Tan dogs are bb.
Again using Punnett's square table theory if both parents are BB (Black and Tan being the dominant gene)
| Genes in gametes | Sperm B | Sperm B | ||
| Egg B | BB | BB | ||
| Egg B | BB | BB |
All offspring will be 100% BB so all Black and Tan
If one parent is Black and Tan which is the dominant gene so BB and one parent is carrying the chocolate as a recessive gene so Bb the offspring are likely to be a mix, 50% Black and Tan and 50% carrying chocolate as the recessive gene.
| Genes in gametes | Sperm B | Sperm b | ||
| Egg B | BB | Bb | ||
| Egg B | BB | Bb |
If both parents are Bb so Black and Tan dogs carrying chocolate the offspring are likely to be a mix of 25% Black and Tan BB, 50% Black and Tan carrying chocolate as the recessive gene Bb and 25% Chocolate and Tan.
| Genes in gametes | Sperm B | Sperm b | ||
| Egg B | BB | Bb | ||
| Egg b | Bb | bb |
Red
Red is a dominant colour. If a dachshund has even one copy of the red gene it will be red no matter what other genes it has. The exception to this is if the dog has two copies of the cream gene in which case it will be cream.
Scientifically the red gene in dachshunds is given the letters Ay.
Dachshunds that have one copy of the Ay gene will be red but will be able to produce puppies of different colours (depending on the other genes they also have). Normally these dachshunds possess the AyAt combination.
Two copies of the At version of the gene (AtAt) will result in dogs with tan points, Black and Tan or Chocolate and Tan.
Dapple
Dapple is a pattern caused by the Merle gene. Scientifically it is identified by a capital letter - M, dapple is a dominant gene.
The dapple gene causes a patchy dilution of the coat colour.
In dachshunds you will often see them referred to as Silver Dapples and Chocolate Dapples but to be technically correct the basic colour should be referred to i.e. Chocolate and Tan dapple. Nellie's father is, as registered on the Kennel Club a Chocolate and Tan dapple.
However if one parent is Dapple but a puppy born from it is not (like Nellie), then the puppy does not carry the Dapple gene. For example, in a litter of five puppies there may be a Red Dapple, a Red, a Chocolate and Tan Dapple, a Chocolate and Tan, and a Black and Tan. Their Mother is a Chocolate and Tan dapple and their Father is a Red but the Chocolate and Tan bitch pup and the Black and Tan pup do not carry the Dapple gene.
To carry the Dapple gene, the coat will also be Dapple.
This is proven in Nellie's line.
Should the Chocolate and Tan bitch have a litter, she can be mated to a Dapple dog because she isn't a Dapple herself, even though her mother and some of her siblings are.
The caveat to this, however, is that 'Dappling' can be as little as one strand of hair, it doesn't need to be an obvious pattern for all to see. It's extremely rare for the pattern not to be visible, but it can happen and every breeder should be aware of this. For instance Dapples should only be bred to reds or creams with caution. A Red Dapple/Cream Dapple is very difficult to distinguish from a Shaded Red/Cream and therefore may inadvertently be bred to another Dapple in the future and produce Double Dapple offspring.
Two Dapples should never be bred together as there is a risk of health issues for instance hearing/sight problems.
For this reason, should a litter be planned from a bitch/dog who has a Dapple parent but doesn't appear to be Dapple themselves a DNA cheek swab to test for the Merle Gene is advised and is wholly responsible.
I obtained my test to confirm whether or not Nellie's coat colour has or does not the Merle gene present from Laboklin. You complete an online form to request the buccal swab kit in the first instance then once complete you send the test back with the order form downloaded.
If you are looking to breed then why not pop by the Furrypeeps Puppy website and download the app
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