The Boerboel is a large dog. The Boerboel has prominent and well-developed musculature over the entire body with buoyant movement an impressive and imposing figure of strength. Males are distinctly masculine, whilst bitches are clearly feminine. The ideal size of a male dog is 66cm lower than 60cm is unacceptable. The ideal height of a bitch is 61cm lower than 55cm is unacceptable. The Boerboel Dog is manageable, reliable, obedient and intelligent with strong protective instincts. The Boerboel is selfconfident and f earless. Uncontrollably aggressive and fearful Boerboel Dog are unacceptable. Any serious deviations and/or combinations of deviations from the Boerboel Breed Standard that affect the dog’s health and/or performance negatively are considered unacceptable and can lead to disqualification in the appraisal ring, at the discretion of a senior appraiser.
It was my pleasure to deliver a series of illustrated lectures in the Republic of South Africa at the invitation of a coalition of the South African Boerboel clubs in January 2011. One seminar was on the subject of hip dysplasia and other orthopedic disorders, and the other was on gait and structure. The first set was in the Johannesburg Pretoria area, and the following weekend it was near Durban on the Indian Ocean coast. Both were attended by enthusiastic groups of novices and experienced breeders representing the three or four Boerboel breed clubs in the country as well as fanciers from Belgium and the United Kingdom. After the slide presentations, we discussed general questions including inheritance of other traits besides orthopedic ones. It is the aim of this article to attempt to clear up some confusion that I recognized as existing in the fancy, about coat and pigment color inheritance.
With such a wide range of experience and scientific knowledge in the field, it was easy to see how different people have different ideas when the subject of allowable colors is brought up. Please realize that I am not trying to steer the Boerboel into any personalpreference path. I have no vested interest in the outcome of your decisions. Instead, I offer an outsider’s view, but also one that is based on over 70 years of experience with dogs, and almost as many years of serious study in the field. It’s always important to define terms. Not so much as to change any one person’s lexicon, as to establish a common language so that all parties know what is meant when words are used.
For example, what is your definition of “color”? How about “pigment”? As long as one’s audience understands the context, the words used will also be understood. Also, it helps if you narrow your field by adding a modifier word, so that you get agreement on what is being referred to when you use terms such as “coat color” or “nose pigment.” Additional confusion can occur when we use the same word for both types of pigmented areas of the body that is, both the hair and non-hair areas. By the way, I trust you understand my American spelling of some words such as color instead of the British “colour.”
Most of the time, I prefer to use that word (color) for the coat, and “pigment” to refer to such outer-integument (skin) areas as the nose bulb, eye rims, lips, footpads, anus, and sometimes nails. But you can use the words interchangeably and still be understood. Before going to South Africa, I did not realize that there were black specimens in the breed. Whether this was in the breed from the beginning, or whether it is widespread or principally one breeder’s production is almost immaterial, as it appears it is in the breed now, and it might be detrimental to the clubs and to the breed if a purge were initiated.
The same can be said for some pigment variations that we call “dilutes.” Most Boerboels I have seen have black-pigmented noses and other integument areas, although the great majority have a base coat color of tan (you can call it fawn or red, or use a few other terms) that ranges from a light coffee to a deep dark hue. White markings may be present, but for now, discount these when speaking of color. They are caused by different genes than those we are talking about for base coat color.
Animals have a pair of genes in every cell that code for a certain characteristic, in this case, color. It is convenient to give an alphabetical nomenclature to them in the places (loci, plural of locus) on the chromosome where those genes are located. Geneticists have not always agreed on what letters to use, but I like the abbreviations or Animals have a pair of genes in every cell that code for a certain characteristic, in this case, color. It is convenient to give an alphabetical nomenclature to them in the places (loci, plural of locus) on the chromosome where those genes are located. Geneticists have not always agreed on what letters to use, but I like the abbreviations or symbols used by Dr. Clarence Little, for the most part, and you can use your own words: “A” might refer to “Agouti” or “All-over” pattern. “B” for Black if capitalized (or subcase “b” for the shade of brown generally called liver). “C/c” for concentration of color. “D/d” for Dark and dilute (blue). E/e for the extension alleles that govern the distribution, if any, of black pigment granules. And there are more.
We find it convenient and helpful to use a diagram such as shown below, to show relative dominance of alleles. Remember that alleles are different variations of the basic genes that are at specific positions on the chromosome, and determine colors sown in the integument. Normally, capital letters are used to represent the most dominant of each series, and the subcase letters under them refer to progressively less-dominant (recessive) forms or alleles of each type of gene. Different geneticists may use slightly different abbreviations, but the relative positions/dominance should be the same in all texts. In almost all literature, you will see a capital letter E used for full expression or extension of black in the coat. The most-recessive allele in this series is e, restricting (refusing) any expression of black. The subcase letter means it is recessive to some other allele. In between, there is ebr for brindle. Some breeds have only one or two of these choices.
Consider the horizontal order of letters in the illustration below to represent different locations along a straightened-out chromosome, and the vertical arrangement to represent decreasing dominance. Choose only one in each vertical column, for each genome (in a sex cell or gamete). The order of dominance is according to Dr. Clarence Little, based on information from similar breeds.
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