Horses with unique coloring will always make us horse crazy people do a double-take. Perhaps for you, it is a big blue roan horse with a black mane and tail. No matter what tickles your fancy, a dark horse with a flaxen mane and tail will always be a jaw-dropper. Have you ever wondered how these majestic horses get their unique coloring? Keep reading to find out the 411.
It all starts with DNA
Do you remember reading, “All You Need To Know About The Dun Horse?” We explained how dun horses acquired their distinct coloring and how the answers could be found in their genetic makeup. Here, horses that have the dark coat colors with a flaxen mane and tail have the silver gene in their DNA which is responsible for the awesome coloring.
The silver gene in horses is a dilution gene that affects the phenotype, or appearance, of certain coats of black and bay. It does not affect the phenotype of horses with a red base coat, however, they can still be carries of the gene. Like the dun gene, the silver gene is also dominant. This means that only one parent must carry the gene for the foal to have it.
The silver appearance
The silver gene is specific for affecting areas of black pigment. If a horse with a back base coat has the silver gene, their mane and tail will be flaxen, and their coat will be diluted to a chocolate brown with or without dapples. A horse with a bay coat will also have a flaxen mane and tail, and their dark points will be lightened. As the horse ages, the dilutions may darken as time goes on. Again, chestnuts and horses with a red base coat color will not have any unique coloring in their appearance.
Beauty with a problem
Horses with the silver gene are beautiful, but unfortunately, their beauty comes with a health problem. These horses typically have Multiple Congenital Ocular Abnormalities Syndrome or MCOA for short. This affects the eye and the severity of it depends on how many copies of the silver gene a horse has. Cysts can form in the eye as well as abnormalities with the retina, cornea, and vision impairment starting earlier in the horse's life.
Because most if not all horses that have the silver gene also come with MCOA, horses that have a parent with the silver gene should be tested. Even horses that have a red coat color and have the silver gene will also have MCOA. For this reason, it is a good idea to test for the silver gene.
The silver gene is known to affect a handful of breeds such as Morgans, Icelandic Ponies, Shetland Ponies, Miniature Ponies, Quarter Horses, and the most common, Kentucky and Rocky Mountain Horses.
Although the silver gene comes with a cost, it still makes horses a stunning sight to be seen. Have you ever seen a horse with the silver gene before? Share with us in the comments section!