by Annamaria Tadlock
Click on photos to enlarge.
This dilution gene, "Z", is most widely called "silver", although in Australia it may be called "taffy". Silver, or "silver dapple", is the most widely accepted term. In the Rocky Mountain Horse breed, it is often called "Chocolate" or "Chocolate Flax".
The silver gene dilutes black, but not red, pigment. This is like the opposite of the cream gene, which dilutes red. Silver does not dilute red pigment, but it is often mistakenly thought to do so.
Silver on a black horse can create a Classic Silver Dapple. The body is a sepia-brown color, the mane and tail are flaxen, and the body is covered in cream-colored dapples.
On black, silver can also create "Chocolate silver", where the body is diluted slighly to a chocolate color, but the mane may be flaxen, or in some cases white. In the Rocky Mountain breed, silver is often called "chocolate" or "chocolate flax", where the chocolate silver color is a desired color.
Silver on a bay creates a "red silver" or a "silver bay". The horse will have a red body (as red is undiluted), and a flaxen mane and chocolate-colored legs. It will look like a bay with a flaxen mane and tail-- and if you look close, you'll see the legs are not black, but a diluted sepia/chocolate color.
Silver on a chestnut doesn't show up; silver can't dilute red pigment. Many horses are mistakenly called "silver chestnuts" because they have the flaxen gene, which creates a flaxen mane and legs on a chestnut/sorrel horse. This is not silver . This is only flaxen.
Silver on chestnut does not create the flaxen-maned, light-legged horse that silver on bay does. Therefore it is possible for the silver gene to "hide" for several generations, if it is carried by chestnut horses. As there is no test for silver, the silver in a chestnut is often discovered by breeding to a black-based horse (black or bay) and a resulting silver foal proves that the chestnut carries the silver gene.
Chocolate silver is the "Z" gene on a black horse, but without the dapples. The body is chocolate colored, the manes and tails flaxen, but the body is not dappled like that of a silver dapple.
Silver on seal brown or black can create a "blue silver"-- a horse that looks almost blue, but has a bluish-flaxen mane and tail. It may create a silver horse with red soft parts (the muzzle, flank, and other areas that are red in a seal brown).
on buckskin will cause the black pigment to be diluted. The body
will remain tan colored, but the legs will be lightened to a chocolate
color and the mane will be partially or completely lightenened
to a flaxen color.
is linked to an eye disorder called ASD (Anterior Segment Dysgenesis).
This genetic disease is carried by many silver horses. Heterozygous
horses (one silver gene) appear to have no problems associated
with ASD, but carry a harmless gene. Some homozygous horses, however,
do have vision problems from ASD. To avoid the problem of ASD,
many breeders will not breed two silvers together.
Use of the terms "Ultimate Horse Site", "The Ultimate Horse Site", "Ultimate Horse", "UltimateHorse", "The Ultimate Horse" have been in use since 2000 and use of variations of our name for any reason is prohibited.