Splashed white or splash is a horse coat color pattern

Pinto horse

A pinto horse has a coat color that consists of large patches of white and any other color. The distinction between "pinto" and "solid" can be tenuous, as so-called "solid" horses frequently have areas of white hair. Various cultures throughout history appear to have selectively bred for pinto...

 that produces pink-skinned, white markings. Many splashed whites have very modest markings

Horse markings

Markings on horses usually are distinctive white areas on an otherwise dark base coat color. Most horses have some markings, and they help to identify the horse as a unique individual. Markings are present at birth and do not change over the course of the horse's life...

, while others have the distinctive "dipped in white paint" pattern. Blue eyes

Equine vision

The equine eye is the largest of any land mammal. Its visual abilities are directly related to the animal's behavior and the fact that the horse is a flight animal...

 are a hallmark of the pattern, and splash may account for otherwise "solid" blue-eyed horses. Splashed white occurs in a variety of geographically divergent breeds, from Morgans

Morgan horse

The Morgan is one of the earliest horse breeds developed in the United States. Tracing back to the stallion Figure, later named Justin Morgan after his best-known owner, the breed excels in many disciplines, and is known for its versatility....

 in North America to Kathiawari

Kathiawari

The Kathiawari is a breed of horse from India, originating in the Kathiawar peninsula. Closely related to the Marwari horse, and resembling both that breed and the Arabian horse from which they descend, the Kathiawari was originally bred as a desert war horse for use over long distances, in rough...

 horses in India. The splashed white pattern is also associated with congenital deafness

Hearing impairment

-Definition:Deafness is the inability for the ear to interpret certain or all frequencies of sound.-Environmental Situations:Deafness can be caused by environmental situations such as noise, trauma, or other ear defections...

, though most splashed whites have normal hearing.

Characteristics

The splashed white pattern is characterized by blue eyes

Equine vision

The equine eye is the largest of any land mammal. Its visual abilities are directly related to the animal's behavior and the fact that the horse is a flight animal...

 and the appearance of having been dipped, feet-first, into white paint. The margins of the white markings are crisp, smooth, blocky, and well-defined. The head and legs are white, and the tail is often white or white-tipped. The underside of the body is white, and a connected white patch often spreads smoothly up either side of the thorax. On its own, the splashed white pattern is seldom responsible for white markings that reach the topline, and so it has been categorized as one of the "overo

Overo

Overo refers to several genetically unrelated pinto coloration patterns of white-over-dark body markings in horses, and is a term used by the American Paint Horse Association to classify a set of pinto patterns that are not Tobiano...

" patterns by Paint horse and Pinto horse

Pinto horse

A pinto horse has a coat color that consists of large patches of white and any other color. The distinction between "pinto" and "solid" can be tenuous, as so-called "solid" horses frequently have areas of white hair. Various cultures throughout history appear to have selectively bred for pinto...

 registries.
As sabino-type

Sabino horse

Sabino is a group of white spotting patterns in horses that affect the skin and hair. A wide variety of irregular color patterns are accepted as sabino. In the strictest sense, "sabino" refers to the white patterns produced by the Sabino 1 gene, for which there is a DNA test...

 markings also originate on the underside, some splashed whites can be mistaken for cleanly-marked sabinos. Both patterns can be present on the same horse, but splashed white markings are crisp and blocky, and horizontally-distributed. In particular, the face markings of splashed whites are straight-edged and bottom heavy, whereas those of sabinos are often tapering or feathered, and often vertical in orientation. The presence of additional white patterning genes can intensify the amount or obscure the characteristics of splashed white markings. The ears are seldom white, though white extending onto the ears is most closely correlated with deafness.

Minimal splashed whites

Breed registries

Breed registry

A breed registry, also known as a stud book or register, in animal husbandry and the hobby of animal fancy, is an official list of animals within a specific breed whose parents are known. Animals are usually registered by their breeders when they are still young...

 for which minimum or maximum white markings are a factor in registration have created imaginary lines to simplify the selection process:

• From the ear, to the eye, to the corner of the mouth, to the chin groove,
• the knee on the foreleg, and
• the hock on the hindleg.

White markings extending past these lines are considered "pinto", "paint" or "colored" while white markings which do not cross these lines are not considered to suggest these traits. However, horses without "excessive white markings" can still have the potential to produce "high white" or distinctly spotted offspring. Splashed white horses are especially well-known for producing generations of "solid" horses, followed by an errant, classically-marked splashed white. Discretely-marked splashed whites are responsible for some families of cropout

Cropout

A cropout, crop-out or crop out is a horse with body spots, including pinto or appaloosa spotting, or "high white" horse markings, with a sire and dam who both appeared to have been solid-colored. There are several variations in the definition, depending on the breed registry involved. There are...

 American Quarter Horse

American Quarter Horse

The American Quarter Horse is an American breed of horse that excels at sprinting short distances. Its name came from its ability to outdistance other breeds of horses in races of a quarter mile or less; some individuals have been clocked at speeds up to 55 mph...

s.

The minimal expression of the splashed white pattern can include few or no white markings at all. When only minimal markings are present, other qualities can belie splashed white. Stars and snips may lopsided, off-center, or otherwise strangely placed. Blazes are usually blocky or straight-edged, and bottom-heavy. Splashed white blazes may also be crooked or skewed to one side. Sabinos with a bold blaze almost invariably have white on the lip or chin, and this is not the case for the facial white of a minimally-marked splash; the upper lip typically remains colored.

Leg markings in a minimally-marked splashed white range from hind coronets to high-whites on all four, or marked hindlegs and unmarked forelegs. While sabino leg markings are often tapering with distal patches, the leg markings on a splashed white are crisp but "straight across" or blunt.

The most reliable identifier of the splashed white pattern is one or more blue, or parti-colored eyes. Splash is a strong candidate especially if blue eyes run in a family without a history of the frame pattern.

Inheritance

The gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

 responsible for the splashed white pattern is not yet identified and has not been mapped, however studies suggest that it is not part of the linkage group

Genetic linkage

Genetic linkage is the tendency of certain loci or alleles to be inherited together. Genetic loci that are physically close to one another on the same chromosome tend to stay together during meiosis, and are thus genetically linked.-Background:...

 that includes roan

Roan (horse)

Roan is a horse coat color pattern characterized by an even mixture of colored and white hairs on the body, while the head and "points"—lower legs, mane and tail—are more solid-colored. The roan pattern is dominantly-inherited, and is found in many horse breeds...

 and tobiano

Tobiano

Tobiano is a spotted color pattern commonly seen in Pinto horses, produced by a dominant gene. The tobiano gene produces white-haired, pink-skinned patches on a base coat color. The coloration is present from birth and does not change throughout the horse's lifetime, unless the horse also carries...

. The KIT gene

CD117

Mast/stem cell growth factor receptor also known as proto-oncogene c-Kit or tyrosine-protein kinase Kit or CD117 is a protein that in humans is encoded by the KIT gene...

 is not thought to be a candidate gene

Candidate gene

A candidate gene is a gene, located in a chromosome region suspected of being involved in the expression of a trait such as a disease, whose protein product suggests that it could be the gene in question...

 for splashed white. Preliminary studies from the early part of the 20th century suggested that splashed white was the result of a recessive gene, however this is no longer believed to be the case. It is more likely that many splashed whites go unidentified, whether because their markings are too minimal to register as "pinto" with breeders, confusion with sabino

Sabino horse

Sabino is a group of white spotting patterns in horses that affect the skin and hair. A wide variety of irregular color patterns are accepted as sabino. In the strictest sense, "sabino" refers to the white patterns produced by the Sabino 1 gene, for which there is a DNA test...

, or the confounding effect of multiple white spotting patterns. These effects also likely account for the apparent lack of homozygous splashed whites, as suspected homozygotes would still produce unremarkably-marked offspring. It seems therefore more likely that splashed white is the result of an incomplete dominant gene, with homozygotes exhibiting the characteristic splashed white phenotype. Just as the presence of additional white patterning

Pinto horse

A pinto horse has a coat color that consists of large patches of white and any other color. The distinction between "pinto" and "solid" can be tenuous, as so-called "solid" horses frequently have areas of white hair. Various cultures throughout history appear to have selectively bred for pinto...

 genes can increase the amount of white, other genes may be responsible for restricting the expression of splash.

Health concerns

Some horses with the splashed white pattern have been shown to have congenital deafness, though many or most have normal hearing. This type of deafness is probably similar to instances of deafness in white or piebald, blue-eyed

Equine vision

The equine eye is the largest of any land mammal. Its visual abilities are directly related to the animal's behavior and the fact that the horse is a flight animal...

 examples in other species. In white-coated cats and dogs with deafness, an absence of melanocyte

Melanocyte

-External links: - "Eye: fovea, RPE" - "Integument: pigmented skin"...

s in the inner ear leads to death of the hair cell

Hair cell

Hair cells are the sensory receptors of both the auditory system and the vestibular system in all vertebrates. In mammals, the auditory hair cells are located within the organ of Corti on a thin basilar membrane in the cochlea of the inner ear...

s, which are necessary for perceiving sound. The presence of pigment around the outside of the ears - which almost all splash horses have - does not indicate a presence of that necessary pigment in the inner ear.
Domestic horses often cope well with deafness, and deaf horses may go undiagnosed. Some deaf horses are more skittish than normal, while others are distinctly calmer. Deafness in horses can be diagnosed by brainstem auditory evoked potential

Brainstem auditory evoked potentials

Brainstem Auditory evoked potentials are very small electrical voltage potentials which are recorded in response to an auditory stimulus from electrodes placed on the scalp. They reflect neuronal activity in the auditory nerve, cochlear nucleus, superior olive and inferior colliculus of the...

 (BAEP), which is minimally invasive and requires no sedation and minimal restraint. While blue eyes and a white face are often associated with deafness in other species, apron-faced, non-splash horses are not known to be deaf. Nor is the presence of one blue, one normal eye indicative of unilateral deafness. The case horse in Hardland's 2006 case study had one blue eye, while the other was parti-colored, but the horse was bilaterally deaf.

Prevalence

The splashed white pattern was first studied in Finnish Drafts

Finnhorse

The Finnhorse or Finnish Horse is a horse breed with both riding horse and draught horse influences and characteristics, and is the only breed developed fully in Finland...

 and Welsh ponies

Welsh Pony

The Welsh Pony and Cob are closely related horse breeds including both pony and cob types, which originated in Wales in the United Kingdom...

 by Klemola in 1933. Klemola's multiple studies on the topic have since been largely discredited, his text describing to detail a pattern now recognised as Sabino

Sabino

Sabino is a municipality in the state of São Paulo in Brazil. The population in 2004 was 5,146 and the area is 312.57 km². The elevation is 412 m....

, and his illustrations featuring horses that according to modern knowledge would be a mixture of splashed whites, tobiano

Tobiano

Tobiano is a spotted color pattern commonly seen in Pinto horses, produced by a dominant gene. The tobiano gene produces white-haired, pink-skinned patches on a base coat color. The coloration is present from birth and does not change throughout the horse's lifetime, unless the horse also carries...

s, sabinos, and combinations of multiple spotting factors. Originally believed to be very rare outside of Europe, splash is turning out to be more common than previously thought. The apparent spike in "new" splashed whites may be due to the pattern's tendency to masquerade as modest markings. In addition, other patterns have a similar look: in particular, some forms of sabino

Sabino horse

Sabino is a group of white spotting patterns in horses that affect the skin and hair. A wide variety of irregular color patterns are accepted as sabino. In the strictest sense, "sabino" refers to the white patterns produced by the Sabino 1 gene, for which there is a DNA test...

 are called "splash" and vice-versa. Since the original study in the early part of the last century, splashed white has been identified in Icelandics

Icelandic horse

The Icelandic horse is a breed of horse developed in Iceland. Although the horses are small, at times pony-sized, most registries for the Icelandic refer to it as a horse. Icelandic horses are long-lived and hardy. In their native country they have few diseases; Icelandic law prevents horses from...

 and Paints, Miniature horse

Miniature horse

Miniature horses are found in many nations, particularly in Europe and the Americas. The designation of miniature horse is determined by the height of the animal, which, depending on the particular breed registry involved, is usually less than as measured at the last hairs of the mane, which are...

s, American Saddlebred

American Saddlebred

The American Saddlebred, formerly known as the American Saddle Horse, is a breed of horse that was developed in Kentucky by plantation owners. Today, in the horse show world, they are most commonly seen under saddle in Saddle seat style riding, and in various types of driving, including pleasure...

s and Morgan horse

Morgan horse

The Morgan is one of the earliest horse breeds developed in the United States. Tracing back to the stallion Figure, later named Justin Morgan after his best-known owner, the breed excels in many disciplines, and is known for its versatility....

s, as well as in the Irish Tinker or Gypsy horse

Gypsy Vanner horse

The Gypsy Horse , also known as an Irish cob , Gypsy Cob, Gypsy Vanner , Coloured Cob or Tinker horse , is a horse breed. The breed originates from the UK and Ireland...

, the Indian Kathiawari

Kathiawari

The Kathiawari is a breed of horse from India, originating in the Kathiawar peninsula. Closely related to the Marwari horse, and resembling both that breed and the Arabian horse from which they descend, the Kathiawari was originally bred as a desert war horse for use over long distances, in rough...

 and feral Abaco Barbs of the Bahamas. Minimally-marked splashed whites have been responsible for cropout

Cropout

A cropout, crop-out or crop out is a horse with body spots, including pinto or appaloosa spotting, or "high white" horse markings, with a sire and dam who both appeared to have been solid-colored. There are several variations in the definition, depending on the breed registry involved. There are...

s among American Quarter Horse

American Quarter Horse

The American Quarter Horse is an American breed of horse that excels at sprinting short distances. Its name came from its ability to outdistance other breeds of horses in races of a quarter mile or less; some individuals have been clocked at speeds up to 55 mph...

s.

External links

• Deaf Horse Association Official Deaf Horse Association's webpage