The
BorderCollies’ coat is visible in many colors; the most common color observed
in the United
States
today is black and white. BorderCollies are becoming more popular here in the
U.S., people are seeing them on
Television and in herding and
agility events as well as many conformation
shows.
There are many hair colors and
patterns in the animal world, one pigmentmelanin, is responsible for hair and
skin color. The hair (and skin) color of both people and pets is entirely
dependent on the amount of pigment that is present. Melanin produced by
melanocytes, special cells in the skin; UV rays, in turn stimulate melanocytes,
which is why people get tan.
There are actually two kinds of melanin: Eumelanin, which
is darker and predominant in black and brunette hair and phaeomelanin, which is
lighter and predominant in red and blond hair. White hair has no melanin of
either kind. Albinos are totally void of pigment anywhere in the body. The
reason for graying hair in aging pets and people is less dark melanin deposited
throughout the growing hair.
The pigment may not be uniformly deposited in
normal-growing hair. More melanin is typically; deposited at the tip of the
hair as it first begins to grow and then melanin in smaller amounts in the rest
of the hair shaft.
There is another influence on hair color found in animals
and not people called the agouti effect. The agouti protein causes alternate
layers, or bands, of each type of melanin leading to a “stacked ring” effect.
This pattern commonly found in rabbits and mice. Agouti hair may appear to be a
shade of gray from a distance while the “stacked rings” can require
magnification to see.
The range of colors produced by melanin is limited to
shades of yellow, brown, red and black. The natural shine to the coat is due
first to a smoothly grown hair with a uniform shaft that does not diffract
light, combined with oils from glands in the skin that are located at the base
of every hair follicle. These follicles coat the hair shaft, filling small
surface imperfections much the way wax does for your automobile.
Multiple genes determine which type of melanin and how much
of each are deposited ultimately influencing coat and skin color. Coat colors
of different domestic animal breeds have evolved from selective breeding to
create a uniform and reproducible gene influence.
All animals inherit
many distinctive characteristics from their parents; genes control these unique,
and inherited, characteristics.
Genes are
submicroscopic particles; hundreds of genes attached in a long string called a
chromosome. Some genes are variable and
some are faux. Each gene
has a dominant appearance and a recessive appearance; so for example, a
puppy may inherit the gene for unyielding
black coat color from his sire and the gene for unyielding red
coat color from his dam. The gene for
unyielding black is dominant and the gene for unyielding red
is recessive.When both genes in
a pair are the same, either dominant or recessive, we say
the dog is homozygous (pure) for that trait or
character and must pass this
characteristic to any progeny. If the genes in a pair are different, the dog is heterozygous (carries a dominant and
a recessive) for that trait and could pass either the recessive or the
dominant gene to offspring.
A litter of puppies
may vary from one another in these characteristics; one may have a rough long
coat of hair and another short or smooth coat. Coat color in one litter may include black and white, red and
white, gold and white, blue and white or perhaps merle. The ears may be carried erect (prick ears)
semi erect or low. Eye color may be lighter or darker. Coat color is not determined by just one gene
but by several genes each with a dominant and a recessive
form.
Genes are Dominate or Recessive
Dominate Genes Recessive Genes
Genes 1 Solid Black Solid Red Genes 2 No Tri-Tan Tri-Tan Genes 3 No Dillute Dilute Genes 4 Merle No Merle
Dominate Color
Recessive Color
Imagine chromosomes as
shapes in a long string. Put all these
shapes in a bag, reach in without looking, and pick out one of each stringed
shape. Here is an example
of
what this might look like.
Puppy # 1
Puppy # 2
Puppy # 3
Puppy # 4
Puppy # 5
Puppy # 6
Puppy # 7
The gene that determines
unyielding black coat color dominates and the red emergence is recessive. The gene determining the display of merle
(marbling) has a dominant form of merle and recessive form of no
merle.
1st picture is black and white color.
2nd picture is blue merle color.
3rd picture is red merle color.
4th picture is chocolate and white color.
5th picture is slate and white color.
6th picture is sable or red and white color.
7th picture is black tri-color.
8th picture is blue merle tri-color.
9th picture is red merle tri-color.
10th picture is chocolate tri-color.
11th picture is sable or red tri-color.
12th picture is slate tri-color.
13th picture is white with black on head.
Black and White
Black and White with Irish Spotting
Black and white with piebald
Blue Merle and White
Black and White Tricolor
Blue Merle and White Tricolor
Black and White Tricolor (lighter)
Blue and White
Blue and White Tricolor
Seal and White
Seal and White Tricolor
Red or Chocolate and White
Red or Chocolate and White Tricolor
Red or Chocolate and White Merle
Red or Chocolate and White Merle Tricolor
Gold and White (lighter)
Gold and White
Sable and White
Slate Merle and White
Slate Merle and White Tricolor
White with minimal black on body
White with Black and Tricolor on Head
White and minimal black on head
White and Black Merle with White Head
White Slate Merle
Pure White no color pigment
Inheritance for Solid Color
The illustrations
below show a dog with two black genes for unyielding coat color mated to a bitch
with one black and one red gene for unyielding coat color. Both dog and bitch
show black and white, because her dominant black gene will mask the bitches’
recessive red gene.
This model shows;
two offspring will inherent two genes for unyielding (dominant) coat color, one
from their sire and one from their dam. The other two offspring will possibly
inherent two genes one black and one red.The genes of their sire and the genes
of their dam, the litter inherit is random.
An idea, (of what
life might offer); genes inherited in the probability below provide each puppy
to receive a black gene from his sire; the sire only has two black
genes to offer. The dam offers
her offspring either a black or a red gene with a 50/50% chance of
either.
All offspring appear
black and white because of the dominant black gene. The black gene masks the red gene that the dam
offers. We cannot tell which
offspring carry the hidden red
gene.
Parents
Sire:Dam: black/white-carries black/white-carries 2 black genes. 1 black and 1 red gene.
Offspring
black/white-carries black/white-carries 2 offspring carries-2 black genes. 2 offspring carries 2 red genes.
It will be impossible to tell if the offspring carry the red gene because all will be black and white in coat color, but knowing that their dam was red would indicate that they all must carry the recessive red gene for unyielding color offspring carry the hidden red gene.
Parents
Sire: Dam: black/white-carries black/white-carries 2 black genes. 2 red genes.
In this illustration, the sire carries two black genes and the dam carries two red genes. Again all offspring appear black and white because of the dominant black gene. The black gene masks the red gene that the dam offers. It will be impossible to tell if the offspring carry the red gene, but knowing that the dam carries two red genes would indicate that most of the puppies carry the red gene.
Offspring
black/white-carries black/white-carries All offspring carries one black and one red gene.
Parents Sire:Dam: black/white-carries black/white-carries 1 black and 1 red gene. 1 black and 1 red gene.
Offspring black/white-carries black/white-carries 1black and 1 red gene. 1 black and 1 red gene. red/white-carries black/white-carries 2 red genes. 2 black genes.
Parents Sire: Dam: black/white-carries red/white-carries 1 black and 1 red gene. 2 red genes.
Offspring black/white-carries black/white-carries 1black and 1 red gene 1 black and 1 red gene red/white-carries red/white-carries 2 red genes 2 red genes
The
Dominate Color
Recessive Color
Puppy # 1
Puppy # 2
Puppy # 3
Puppy # 4
Puppy # 5
Puppy # 6
Puppy # 7
1st picture is black and white color.
Black and White
Black and White with Irish Spotting
Black and white with piebald
Blue Merle and White
Black and White Tricolor
Blue Merle and White Tricolor
Black and White Tricolor (lighter)
Blue and White
Blue and White Tricolor
Seal and White
Seal and White Tricolor
Red or Chocolate and White
Red or Chocolate and White Tricolor
Red or Chocolate and White Merle
Red or Chocolate and White Merle Tricolor
Gold and White (lighter)
Gold and White
Sable and White
Slate Merle and White
Slate Merle and White Tricolor 
White with minimal black on body
White with Black and Tricolor on Head
White and minimal black on head
White and Black Merle with White Head
White Slate Merle
Pure White no color pigment
