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Окрасы английского кокера
"Color. Various. Parti-colors are either clearly marked, ticked or roaned, the white appearing in combination with black, liver or shades of red. In parti-colors it is preferable that solid markings be broken on the body and more or less evenly distributed; absence of body markings in acceptable. Solid colors are black, liver or shades of red. White feet on a solid are undesirable; a little white on throat is acceptable; but in neither case do these white markings make the dog a parti-color. Tan markings, clearly defined and of rich shade, may appear in conjunction with blacks, livers and parti-color combinations of those colors. Black and tans and liver and tans are considered solid colors." - Official Breed Standard for The English Cocker Spaniel, approved by the American Kennel Club, October 11, 1988
English Cocker Spaniels are colorful but the outcome of those colors comes from a wide range of genes. These genes combine to determine two things - the coat color (black, red and liver) and the coat patterns (solid and parti-color). Parti-color is further broken down to "roan", "ticked", and "open marked" in order of dominance.
All of these factors are due to a recognized color series (loci, that is, locations on the chromosomes) in dogs. The generally recognized color series' are A(agouti), BC (Chinchilla series), D (blue dilution) E (extension which is responsible for red color in English Cockers), G (graying), M (merle), R (roaning), S (white spotting) and T (ticking.) In most cases multiple loci will work together so several different genes can be used in combination to produce a color. A gene may even mask the presence of another gene. (brown),
In genetics there is Phenotype, or how the dog looks physically, and Genotype, the genetic makeup of the dog, which may or may not be totally expressed in the phenotype. In addition, there are genes which are more dominant than others and are thus called Dominant (which are represented in charts with a Capital letter) and others which are not as strong in expression which are called Recessive (which are represented in charts with a Lowercase letter). Each dog receives one set of genes from each parent. It is the combination of these many genes which are responsible for not only coat color but ear length, darkness and shape of eyes and the dog's entire conformation and quite often health as well.
Take a look below at the variety of colors available in English Cocker Spaniels. Short descriptions of how the genes work give an idea of how these colors and coat patterns have been recorded in the genotype. Many of our understandings about color genetics come from a book by Clarence C. Little titled The Inheritance of Coat Color in Dogs. Today, researchers are still trying to answer many questions about dominance relationships, new alleles, gene series, modifying factors, etc. Additionally, coat color can also be affected by conditions in the womb. There is not yet a definitive understanding of coat color.
Loci in Coat Color
Black and Liver. For English Cockers this loci is B, the brown series. The series allows the production of black pigment. The genes for black (B) and liver (b) are the same gene with black being dominant. A bb dog produces brown pigment wherever the dog would have produced black, affecting not only coat color but also the color of the skin, eye rims and nose.
Red. The gene for red is not the same as the gene for black and liver. The loci is E, the extension series. This series includes Ed (dominant black), E (normal extension) and e (recessive red.) Thus, a red is produced by having two (ee) recessive red genes. The skin and eye color generally show through normally but some ee dogs will show reduced pigment on the nose. They also seems to be more heavily affected by any gene modifier that reduces pigment. Solid reds have something like a 30% higher chance of retaining white on their face than black or liver puppies do, and red/orange parti-colors tend to have more overall extension of white than black or liver do.
If a dog carries E, the dominant gene for "no red", it will be black coated (unless it also carries the two recessive genes for liver, in which case it will be liver coated).
Red/Orange in Parti Colors. The same loci (ee) recessive red will produce a red in the parti colors that appears lighter. It is then registered as orange. Although, the loci is the same (B, ee) they will be registered as orange in parti colors. Occasionally the red will be darker like an Irish Setter or Welsh Springer Spaniel. In these cases, the parti-color will be either red roan or red and white.
Lemon and Golden.
Lemon, a light orange, can appear almost yellow or buff. Lemon is a
dog (ee) that also has the loci for liver (bb.) So a
must have have two recessives, the one that gives the red color (ee)
and the one that gives the liver color (bb.) The two recessives
lighten the coat color to lemon. There are other genetic factors such
as the "chincilla" gene and genetic modifiers that act together with
liver gene to cause the yellow markings. A genetically solid lemon will
be registered in English Cocker Spaniels as either a red (who has a
nose) or golden. A lemon with any other coat pattern will be registered
with "lemon" in the name such as lemon roan.
The solid coat pattern is determined by the loci S, solid color. This is the normal gene in breeds without white markings. An SS dog can completely lack white, but it can also express very minor white markings such as a white streak on the chest. Since S, solid color is dominant, a solid can carry for parti-color, but a parti-color cannot carry for solid. A solid carrying two genes for solid can only produce solid and bred to a parti-color will only result in solid color puppies, but all those puppies will be carriers for parti-color. If a solid that carries a gene for parti-color is bred to a parti-color, some puppies will be solids and some will be partis, but all the solids will carry for parti-color.
The loci is R, roan. The nature of the coat pattern and the progressive development of dark hair in a light area is unclear and still in debate. Roan is defined as "having the base color (as red, black, or brown) muted and lightened by a mixture of white hairs."
Roan (R) appears to be dominant to (rr) non-roan, i.e. open marks. Roan can carry for open marks, but open marks cannot carry for roan.
Open marked colors may also have "ticking" in the coat. Ticking are flecks of color in areas where the coat would have been white. When ticking occurs between patches, they are registered as color, white and ticked. The loci is T, ticking. T (ticking) is dominant over (t) lack of ticking. The amount and location of ticking are greatly affected by genes for size, shape and density of the ticking.
There is disagreement on whether ticking is the same as roaning or not. Both can occur on the same dog, although roaning plus open marks cannot.
An open marked dog will lack ticking or roaning in the coat. An open marked dog will have clear white between patches. When ticking occurs between patches, they are not truly open marked but registered color, white, and ticked. Lack of ticking (tt) is recessive to roan and ticking. So, a roan can carry for open marks, but open marks cannot carry for roan.
Any coat color or pattern can have tan markings which will appear on the muzzle, over the eyes, on the chest, on the legs and under the tail. The tan is loci (A) Agouti with the allele being (at). Parti-colors can also be (at) but the coat pattern will remain the same.
Tan is recessive. So, a dog which is itself tan must have received the (at) loci from both parents. A dog may produce a tan without showing tan marking if it has received one (at) from a parent and is mated to another dog with the (at) as well.
Can a red or orange have tan marking? Yes. A red or orange that is the product of two tan-marked parents carries two genes for tan. Therefore it is genetically a "red and tan" or "orange roan and tan" but phenotypically, it is not observed.
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