Tri color is a breed standard adopted by the AKC. It was developed in 1989 and it defines the physical characteristics of each dog. The term “tri” refers to three colors: black, white and brown. These are the most common colors in this breed. There are other shades such as silver, blue merle, yellow merle, pink merle and even orange merle dogs. All these colors have their own unique traits which make them desirable for different purposes.
The term “color” refers to the markings or coloring of the dog. Some of these include spots, stripes, patches, spots and other patterns. Most commonly, there are two types of markings: solid and patterned. Solid markings are those without any shading or blending together; they remain distinct from one another throughout the entire body of the dog. Patterned markings may be either solid or patterned but they must blend into each other to form a recognizable pattern.
The word “pattern” refers to the arrangement of markings. Patterns may be random or they may be arranged in some way that makes them distinguishable from one another. Random patterns are those that do not follow a specific pattern. For example, if a dog has five horizontal stripes and four vertical bars, then the patterning would consist of alternating stripes and bars. Patterned markings are those that follow a specific pattern but the pattern does not necessarily consist of any more than two types of markings.
For example, if a dog has a solid black head, a patchwork of black and white diamonds down its back and a white stomach, then the pattern would consist of stripes, bars and a central patch.
The term “merle” refers to a specific type of patterned marking. It is said to be the result of a specific type of gene mutation. The two terms are often used interchangeably but they represent different things. In order to be considered a merle dog, it must have at least one blue eye and it must have a specific type of patterning. A dog with this condition will typically have a splotchy or patchwork coloration over most of its body.
The patches will also often have a muted color compared to the rest of the dog. The patches themselves will also often have a random arrangement.
Another commonly seen trait in merle pigmentations is the “ghost markings”. These are the faint remnants or outlines of other markings that can still be made out even though they are not fully present. For example, a dog with merle markings may still have faint traces of stripes showing even though it has been covered by other patches. These ghost markings are not limited to just stripes however, it can also consist of spots or patches as well.
The merle gene is what causes the merle coloring in these dogs and is one of several types of “dilution” genes that can produce similar results. Dilution genes affect the amount of color pigment laid down in the hair. When more than one dilution gene is present, then the effect is an even greater decrease in pigment, which is why these dogs often have blue eyes and muted colors.
The merle gene is also known as the D/M gene and it comes in two forms: D for Dominant and M for Recessive. All dog’s have at least one of these genes and most can have two. Since there are two versions of the gene, this means that there are four possible combinations of them. These combinations have different effects on the appearance of the dog when they are present.
The first combination consists of a dog that has two copies of the recessive version of the gene. This will cause the dog to only be colorblind (D/d), but not display any merle markings (DM/m).
The second combination consists of a dog that has two copies of the dominant version of the gene. This causes the dog to display merle markings (D/D), but not be colorblind (M/m).
The third combination consists of a dog that has one copy of each version of the gene. This combination causes the dog to be colorblind (D/M), but not display merle markings (M/m).
The final combination consists of a dog that has two copies of the recessive version of the gene. This will prevent the dog from being able to see any additional colors beyond those that can be seen by humans (d/d), but it will not display merle markings (d/m).
When breeders want to create a merle Great Dane, they will often times intentionally select for the d/M combination. This makes it so that the dog will have the merle markings, but will not be affected in any other way by the gene. It is also important to remember that two such merles can produce a normal colored offspring.
Sources & references used in this article:
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