We’ve talked about the allure of palomino horses and explored facts about chestnuts, but today let’s turn our attention to horses of yet another delightful color: gray. With their stunning beauty and fascinating genetics, gray horses have delighted horse enthusiasts for centuries. Let’s take a closer look.
- Gray horses have one or two copies of the gray gene. A horse with one copy of the gray gene is said to be heterozygous for gray and can potentially produce gray OR non-gray offspring, depending on whether or not the gene is passed on. A horse with two copies of the gray gene is said to be homozygous for gray and all of the horse’s offspring will turn gray, without exception. This is because the horse does not possess a non-gray gene and therefore can only pass gray.
- Gray can be spelled g-r-e-y- or g-r-a-y. Some breed associations prefer grey, others prefer gray. The University of California-Davis Veterinary Genetics Laboratory uses gray.
- A gray horse can be born any color. There’s a common misconception that all gray horses are born black. Not so! A gray horse could conceivably be born ANY color. (It’s interesting to note, however, that when a black foal is going to go gray, it is usually born a deep, jet-black. Black foals that do not carry the gray gene are often born a mousy-gray color, which is why people sometimes joke that “black horses are born gray, gray horses are born black.”)
- Gray is a modifier. Gray modifies the base coat color, transforming it to gray. Genetically, the horse is the color it appeared at birth, but the presence of the gray gene modifies the coat color to gray.
- A gray horse must have at least one gray parent. The gray gene is a dominant gene and cannot “show up” later on, as recessive genes are wont to do. So if your horse is gray, you know without question that one or both of its parents were gray.
- Gray horses keep life interesting thanks to the myriad shades of this color from “rose gray” and “dappled” to “flea-bitten” and “pure white.” It’s a transformative process that can take many years.
- Gray horses are found in many breeds. The color is commonly associated with the Lipizzan breed, but it is also very common in Andalusians, Arabians, Welsh Ponies, and is accepted as a color by most breed registries.
- Gray horses have won the Kentucky Derby on eight occasions. These famous gray Thoroughbreds include: Determine, Decidedly, Spectacular Bi, Gato Del Sol, Winning Colors (a filly), Silver Charm, Monarchos, and—most recently—Giacamo in 2005.
- The only Kentucky Derby winner to be disqualified was a gray. The gray horse Dancer’s Image, initial winner of the 1968 Kentucky Derby, was later disqualified after a drug test showed the presence of phenylbutazone. The disqualification remains a topic of controversy even today.
- The Horse in the Gray Flannel Suit, the 1968 Disney comedy starring Dean Jones and Kurt Russell, features a gray horse named Aspercel.
Silver Charm, winner of the 1997 Kentucky Derby and Preakness Stakes, now resides at Old Friends Thoroughbred Retirement Farm in Georgetown, Kentucky.
Samantha Johnson is a freelance writer and the author of several books, including The Field Guide to Horses, (Voyageur Press, 2009). She raises Welsh Mountain Ponies in northern Wisconsin and is a certified horse show judge. Follow her on Twitter: @miraclewelsh.