Breeding for Dilute Colors, continued ...
Champagne
The champagne allele is rare. It is dominant and lightens
all colors. At birth, a champagne foal always has pink skin and
blue eyes. The coat is usually dark, but lightens with age. Its
eyes may gradually turn green or amber. The skin may darken to
a pumpkin or purple shade, often with freckles.
The champagne allele, when combined with black, lightens it
to a color similar to the slate of a grullo dun, but without
the primitive marks. Champagne lightens bay to amber with dark
points, very much like buckskin.
A champagne sorrel can be gold all over, or gold with a white
mane and tail like a palomino.
When combined with the cremello or silver dapple alleles,
a champagne horse may look like a cremello.
There is no genetic test for the champagne allele. However,
pink to purplish skin and eyes ranging from blue to amber are
reliable signs of champagne.
Silver Dapple
Silver dapple is rare except in a few breeds, notably Icelandic
and Rocky Mountain horses, and Shetland ponies. It is a dominant
allele that lightens black to colors ranging from flaxen to chocolate
brown. It leaves red on the body unchanged, but on the mane and
tail it lightens red to flaxen. Silver dapple horses may be confused
with sorrels, palominos, or buckskins. A tip-off to the allele
is that a silver dapple always has white eyelashes.
Doubling the silver dapple allele does not increase the dilution.
Thus, you cannot tell whether a horse is homozygous just by looking.
It is not a good idea to breed for homozygous silver dapple because
such horses tend to have poor vision.
There is no genetic test for the silver dapple allele.
Compound Dilute Colors
The dun, cremello, champagne and silver dapple alleles can
all appear together in one horse. Cremello with champagne creates
a shade of crème, and looks very much like homozygous
cremello. Silver dapple plus cremello can look like champagne
or crème. Combinations that include cremello, champagne
or silver dapple can also throw a faintly yellow body with pale
brown mane and tail. Except for the missing lineback, such a
horse looks like a claybank dun.
Dun with other dilution alleles, even with homozygous cremello,
can be very light yet still show a faint lineback and other primitive
marks. These are called cream duns or white duns.
Summary: Your Best Breeding Bets
100% Certain Breedings:
For a palomino, breed a sorrel with light mane and tail whose
color is caused by homozygous chestnut to a homozygous cremello
that is also homozygous chestnut.
For a crème, breed one homozygous cremello to another.
Good Breeding Bets:
You can be almost 100% certain of getting a buckskin if one
parent is homozygous cremello, either parent is homozygous bay
and no more than one parent carries a recessive black allele.
A homozygous lineback dun will throw linebacks with 100% certainty
if bred to any other color. Because there is no genetic test
for homozygous dun, your best bet is to use a stallion that has
thrown only linebacks.
Homozygous champagne will throw champagnes with 100% certainty
if bred to any other color except a cremello crème. Because
there is no genetic test for homozygous champagne, your best
bet is to use a stallion that has thrown only champagnes even
when bred to non-champagne horses.
A buckskin that is homozygous bay will throw 50% buckskins
if bred to a sorrel or bay, and will not throw cremellos.
A palomino can throw 50% palominos if bred to a sorrel and
will not throw cremellos.
If you breed a silver dapple to a non-silver dapple (make
sure the eyelashes are not white), you should avoid getting a
nearly blind foal. Depending upon whether the silver dapple is
homozygous, you will get either a 100% or 50% chance of a silver
dapple foal.
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Resources:
University of California at Davis tests for bay, recessive
black, chestnut and cremello: http://www.vgl.ucdavis.edu/service/horse/coatcolor.html
International Champagne Horse Registry
ICHR
PO Box 4430
Paso Robles, CA 93447-4430
http://www.ichregistry.com/
American White Horse and Crème Horse Registry
90,000 Edwards Road
Naper, NE 68755
402-832-5560
http://www.whitehorseranchnebraska.com/registry.htm
Equine Color Genetics, by D. Phillip Sponenberg, 2nd ed. (Iowa
State Press, 2003)
