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Working cockers do come in quite a wide variety of different colours and patterns.
The principles of colour genetics are the same for all breeds so a lot of this is common to both the Cockers and Border Collies.
We’ll start again with the basics…
I will try and describe this in the simplest way as I understand it but it is worth remembering that while the understanding of colour genetics is very useful when wishing to breed puppies of a particular colour, the colour should be the last consideration when planning a mating...the breeders’ requirements for health, temperament and type must all be fulfilled before colour is taken into account and when you find all the things you want, the colour is the icing on the cake!
Ok...here we go...
The hair follicles are made up of cells containing two colour pigments – eumelanin (black) and phaeomelanin (true red); so basically eumelanin is the pigment that produces the darker black and brown shades, phaeomelanin produces the true red (golden red). There are a vast number of genes that control the production of these pigments within the cells and therefore control coat colour.
Firstly remember that there are always two of every controlling gene, one comes from the sire and one from the dam. Where a gene is expressed as a capital letter it is dominant, where it is lower case it is recessive.
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Where an animal has two identical genes this is called homozygous and where they are different it is heterozygous.
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Where a gene is dominant the animal only needs a single copy from either parent to express that colour. Where a gene is recessive an animal MUST have two copies of that gene in order to express that colour; so they must get one copy from either parent. In this way recessive genes can be ‘carried’ i.e. the animal only has one copy so does not express that colour but has the gene to pass on to it’s offspring.
Where an animal is heterozygous for a particular gene (i.e has one of each) it will statistically pass the dominant copy to 50% of it’s offspring and the recessive copy to the other 50%. Where an animal is homozygous for a particular gene (i.e. has two copies the same) it will always pass this copy on to ALL it’s offspring.
In the simplest terms…
Brown/chocolate, gold/lemon/orange, tan points and particolour markings are all recessive genes.
This means that…
1) Both parents must carry the gene for each colour in order for it to be produced in a litter
2) Any dog exhibiting a recessive colour will pass the gene for that colour on to ALL its’ offspring
And now for the science part…
So lets say a ‘normal’ animal is black…in a chocolate/brown/liver animal (call it what you like, it's all the same colour!) the eumelanin pigment granules are a slightly different shape which makes the coat appear brown. The gene said to be controlling this is expressed as B for black and b for brown. Brown is a recessive gene so both parents must have the gene to produce it in a litter, Black (B) is dominant and where present it will always be expressed.
So…
a brown/chocolate dog will be bb (homozygous brown)
a black dog carrying brown/chocolate will be Bb (heterozygous black)
and a black dog not carrying brown/chocolate will be BB (homozygous black)
A brown/chocolate dog only has this gene to pass on so all its’ offspring will be brown carriers regardless of their own physical colour.
It is the extension gene that is responsible for producing the true red (golden, lemon, orange) colour. While this comes in the variety of different shades ranging from the palest blonde to the deepest russet…it is all the same gene.
The extension gene controls the extension of the two pigments in the hair follicle. ‘E’ is dominant and allows the extension of eumelanin, so the dog is black or brown… ‘e’ is the recessive form and allows the extension of phaeomelanin but prevents the extension of eumelanin, so there is no eumelanin in the pigment and therefore the animal is red. The red colour is produced from a recessive gene so the same principles apply, a dog must be homozygous to exhibit the colour and must get one gene from each parent.
So… true red (golden, lemon, orange) - ee (homozygous red)
carrying true red - Ee (heterozygous non-red)
not carrying true red - EE (homozygous non-red)
What is interesting about this gene is that it will mask the dogs ‘real’ colour. As such you can get black, chocolate and tan pointed dogs that all appear as simply red because of the lack of eumelanin in the hair follicles. As it only affects the hair follicles and not other pigmentation the dogs’ nose and eye rims will express its hidden colour.
The agouti gene is the one responsible for producing tanpoints in cocker spaniels…there are numerous alleles of this gene which vary from breed to breed but the simple tan pointed pattern is the only one that concerns cocker spaniels which makes life much simpler!
This gene is expressed as ‘at’ (agouti – tanpoint)
As we already know each individual has two copies of each gene, when tan points are present the dog must have two copies of the tan pointed gene on the agouti allele
i.e. atat - tanpointed
But...it doesn't end there...there is another gene that effectively switches the agouti genes on and off...this is referred to as dominant black and is written as 'K'
So an animal must also be double recessive for this gene for the tan pointed pattern to be expressed.
KK - Homozygous dominant black, cannot be or produce tanpoint regardless of the A alleles
Kk - Heterozygous dominant black, cannot be tanpointed but can produce the patterns it carries on the A alleles
kk - Homozygous, will exhibit tanpoint depending on it's A alleles
In conclusion...
KK atat – this animal is not tanpointed and cannot produce tanpoint but can pass the tanpoint gene on to its’ offspring
Kk atat - carries tanpoint, can both produce it in a litter and pass it on to its’ offspring
kk atat - tanpointed coat colour, can both produce it in a litter and will pass the gene on to ALL its’ offspring.
This is the gene responsible for particolour i.e. ‘something’ and white and is thought to have numerous alleles in different breeds.
‘S’ is the dominant gene and is just solid colour with no or minor white markings (toes, tail tip, chest, blaze etc). These small white markings are considered a fault in the show ring so show breeders always breed true for EITHER solid or particolour (i.e. no solid to particolour matings)
'sp' is the piebald gene and is the one thought to be responsible for particolour in cockers, this is a recessive gene so a dog must have two copies of the gene to express particolour markings.
S S = solid coloured, no particolour carried
S sp = solid coloured but carrying the gene for particolour
sp sp = particoloured
Where particolour is present a dog will either exhibit open marks or roan. Open marked animals will usually exhibit some ticking, although clear open marks can be seen, they are quite rare.
Roan (R) is dominant to non-roan (rr) so where this gene is present a parti-coloured cocker will always exhibit roaning.
R R = roan
R r = roan carrying the gene for open marks
r r = open marked particolour
Let’s take Drake as an example…
Image: Drake
Drake is black/tan, his father is liver and his mother is blue roan therefore we know he is…
Bb – black carrying brown
kk atat – tan pointed
Ssp RR – solid coloured carrying the gene for particolor, in this case just roan
(we don’t know whether he is carrying the gene for open marks as well as roan but we can probably assume he doesn’t)
This theory has been proven, Drake was mated to a liver/tan bitch, they produced 7 pups…4 liver/tan and 3 black/tan. It is apparent then that this bitch probably does not carry particolour.
Drake was then mated to Teal, a blue roan and tan bitch, they had 6 puppies…4 black/tan and 2 blue roan/tan.
Proving then that Drake does carry both liver and roan as we expected.
Below are some examples of the different colours possible within working cockers.
I must thank everyone that has allowed me to use pictures of their dogs to illustrate the different colours but please be aware that these pictures do belong to the photographer and must not be copied or distributed in any way.
Image: Switch
This is Switch, FTW Rowston Simone, owned by Nick and Kris Cook at Dever Valley Gundogs
Switch is solid black coloured
Image: Bramble
This is Bramble, Fourlanes Alena of Summervilles
Bramble is solid black with a white bib
Image: Isla
This is Isla, Gibble Danette of Summervilles
Isla is solid black with tan points
Isla must have two copies of the recessive tanpoint gene (atat) and she will pass one copy of this gene on to all of her offspring.
Image: Maizy
This is Maizy, Bryning Makin’ Merry
Maizy is solid black with tan points and a white bib and 'blaze'
Maizy must have two copies of the recessive tanpoint gene (atat) and she will pass one copy of this gene on to all of her offspring.
Image: YoYo
This is YoYo, she is black and white, open marked with a small amount of ticking.
YoYo must have two copies of the recessive particolour gene (spsp) AND two copies of the recessive open marked gene (rr), she will pass one copy of each of these genes on to all of her offspring.
Image: Jade
This is Jade, Cumwell Teal, owned by Jacqui Jones at Barrackswood Cockers
Jade is blue roan
Jade must have two copies of the recessive particolour gene (spsp) but she must be either heterozygous or homozygous for the dominant roan gene (Rr or RR). She will pass one copy of the particolour gene on to all of her offspring.
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This is our own Teal, Cracoe Amy at Bryning
Teal is blue roaned with tan points
Teal must have two copies of the recessive particolour gene (spsp) but she must be either heterozygous or homozygous for the dominant roan gene (Rr or RR). She will pass one copy of the particolour gene on to all of her offspring.
Teal must also have two copies of the recessive tan point gene (atat), she will also pass one copy of this gene on to all her offspring.
Image: Paddy
This is Paddy, Wetlands Skipper – owned by Michelle Martin
Paddy is solid liver coloured
Paddy must have two copies of the recessive brown gene (bb), he will pass one copy of this gene on to all his offsrping.
Image: Ruby
This is Ruby, Springfizz Gem at Raezhaven
Ruby is solid liver with a white bib
Ruby must have two copies of the recessive brown gene (bb), she will pass one copy of this gene on to all his offsrping
Image: Trouper
This is Trouper, Breezybrook Trouper
Trouper is solid Liver with tan points
Trouper must have two copies of the recessive brown gene (bb) AND two copies of the recessive tan point gene (atat), he will pass one copy of each of these genes on to all his offspring.
Image: Toffee
This is Toffee, Summervilles Cairistiona
Toffee is solid liver with tan points and a white bib
Toffee must have two copies of the recessive brown gene (bb) AND two copies of the recessive tan point gene (atat), she will pass one copy of each of these genes on to all her offspring.
Image: Holly
This is Holly, Contact Dancer, owned by Jacqui Jones at Barrackswood Cockers
Holly is liver and white, open marked with a small amount of ticking
Holly must have two copies of the recessive particolour gene (spsp) AND two copies of the recessive open marked gene (rr) AND two copies of the recessive liver gene (bb) she will pass one copy of each of these genes on to all of her offspring.
Image: Travis
This is our own Travis, Raezhaven Bryce at Bryning
Travis is liver roan
Travis must have two copies of the recessive particolour gene (spsp) but she must be either heterozygous or homozygous for the dominant roan gene (Rr or RR). Travis must also have two copies of the recessive brown gene (bb); he will pass one copy of the particolour gene and one copy of the brown gene on to all of his offspring.
Image: Dotterel
This is Dotterel, Barrackswood Nutcracker
Dotterel is liver roaned with tan points
Dotterel must have two copies of the recessive particolour gene (spsp) but she must be either heterozygous or homozygous for the dominant roan gene (Rr or RR). She must also have two copies of the recessive brown gene (bb) AND two copies of the recessive tanpoint gene; she will pass one copy of each of these genes on to all of her offspring.
Image: Drew
This is Drew, Larford Ready of Summervilles
Drew is solid gold coloured
Drew must have two copies of the recessive extension gene (ee) which make him appear gold, he will pass one copy of each of these genes on to all his offspring.
Image: Pie
This is Pie, Northwalden Banoffee Pie of Paoates
Pie is solid gold with a white bib and 'blaze'
Note that Pie has liver pigmentation so she is a liver based gold.
Pie must have two copies of the recessive extension gene (ee) which make her appear gold but she must also have two copies of the recessive brown gene (bb); she will pass one copy of each of these genes on to all her offspring.
Image: Fern
This is Fern, Calkerry Roach at Raezhaven
Fern is Lemon and White, open marked with a small amount of ticking
Note that Fern has liver pigmentation so she is a liver based lemon & white.
Fern must have two copies of the recessive extension gene (ee) which make her appear gold but she must also have two copies of the recessive brown gene (bb) AND two copies of the recessive particolour gene (spsp) AND two copies of the recessive open marked gene (rr) so I guess she's pretty rare! Fern will pass one copy of each of these genes on to all her offspring.
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