A cropout, crop-out or crop out is a
horse
The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 mi ...
with body spots, including
pinto or
leopard complex
The leopard complex is a group of genetically related Equine coat color, coat patterns in horses. These patterns range from progressive increases in interspersed white hair similar to Gray (horse), graying or Roan (horse), roan to distinctive, Da ...
spotting, or "high white"
horse markings
Markings on horses are usually distinctive white areas on an otherwise dark base equine coat color, 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 no ...
, 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
A breed registry, also known as a herdbook, studbook or register, in animal husbandry, 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 w ...
involved. There are multiple genetic reasons that may cause a horse to be a cropout. Sometimes solid-colored horses throw cropouts because some spotting patterns are
recessive genes that are not necessarily expressed unless the relevant
allele
An allele is a variant of the sequence of nucleotides at a particular location, or Locus (genetics), locus, on a DNA molecule.
Alleles can differ at a single position through Single-nucleotide polymorphism, single nucleotide polymorphisms (SNP), ...
is inherited from both parents. Other times a gene may be a
dominant or incomplete dominant but so minimally expressed that the horse looks solid but can pass flashy color on to its offspring.
The term originally came about because excess white in certain breeds was considered an undesirable trait and such foals were deemed ineligible for registration, making them
grade horses of little economic value. However, many people liked the flashy color, others sought to keep cropout horses from becoming worthless, and thus new breed registries formed, such as the
American Paint Horse Association The American Paint Horse Association (APHA) is a breed registry for the American Paint Horse. It is currently headquartered in Fort Worth, Texas. .
[Piercy, Janet. "The Colorful World of Paints and Pintos"](_blank)
. The International Registry of Colored Horses, L.L.C. Web site accessed May 25, 2008 In recent years, as
DNA
Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...
testing has become available to verify parentage, breed registries that once excluded cropouts are now accepting them.
The term "cropout" is today most closely associated with horses of
American Quarter Horse
The American Quarter Horse, or Quarter Horse, is an American breed of horse that excels at sprinting short distances. Its name is derived from its ability to outrun other horse breeds in races of or less; some have been clocked at speeds up to ...
breeding.
[Walker, Dawn. "Lethal Whites: A Light at the End of the Tunnel" ''reprinted from: Paint Horse Journal'', February, 1997](_blank)
Web page accessed May 25, 2008 These horse are often registered as
American Paint Horse
The American Paint Horse is a breed of horse that combines both the conformational characteristics of a western riding, western stock horse with a pinto horse, pinto spotting pattern of white and dark equine coat color, coat colors. Developed f ...
s, where the term usually refers to horses with
overo coloring and whose parents were solid horses not registered with the APHA.
["The American Paint Horse - Birth of a Breed" ''from Horse Previews Magazine,'' February, 1997.](_blank)
Web page accessed May 25, 2008 It may also refer to
sabino-patterned horses.
For a cropout horse to be registered as a Paint, both sire and dam must either be Quarter Horses registered with the
AQHA
The American Quarter Horse Association (AQHA), based in Amarillo, Texas, United States, is an international organization dedicated to the preservation, improvement and record-keeping of the American Quarter Horse. The association sanctions many ...
, or
Thoroughbred
The Thoroughbred is a list of horse breeds, horse breed developed for Thoroughbred racing, horse racing. Although the word ''thoroughbred'' is sometimes used to refer to any breed of purebred horse, it technically refers only to the Thorough ...
s registered with
The Jockey Club, plus have coloring that qualifies it for the regular registry of the
APHA. Since the AQHA modified its "white rule" to allow registration of cropouts as Quarter Horses, the APHA has also limited its registration of cropouts to those foaled prior to January 1, 2005.
["How To Register A Cropout"](_blank)
web page accessed May 25, 2008
Cropouts also occur when two solid-colored Quarter Horses produce a foal with
Appaloosa coloring.
[ Holmes, Frank. "Builders of the Breed Wapiti: The Mystery Horse That Wasn't" ''originally published in the Appaloosa Journal'', June 1987, Vol 42, No. 6](_blank)
Web page accessed May 25, 2008 The
leopard
The leopard (''Panthera pardus'') is one of the five extant cat species in the genus ''Panthera''. It has a pale yellowish to dark golden fur with dark spots grouped in rosettes. Its body is slender and muscular reaching a length of with a ...
(Lp) gene that creates the distinctive spotting pattern of the Appaloosa has several variations, including the
Varnish roan, which may appear to be simple
roan coloring to many observers. Thus, the foundation bloodlines of the American Quarter Horse contained some horses who carried the Leopard gene, particularly those from the breeding program of an individual named Coke Roberds.
Though the term "cropout" is most closely associated with Quarter Horses, other breeds, such as the
Morgan horse
The Morgan horse is one of the earliest horse breeds developed in the United States. Tracing back to the foundation bloodstock, foundation sire Figure (horse), Figure, later named Justin Morgan after his best-known owner, Morgans served ma ...
, use the term to describe horses with bold white markings, such as leg markings that up the legs to the belly with irregular, lacy and jagged edges. While the APHA is only open to horses of Thoroughbred and Quarter Horse ancestry, some strongly marked sabino Morgans have been double-registered as
Pintos.
[White, Sue. "The Newest Morgan Color: PINTO"](_blank)
Color Morgan. Web site accessed May 25, 2008
The
overo gene is one of the most frequent genetic sources of cropouts in Paint horses, as there are some forms of overo that are
recessive genes, and a significant number of cropout Paints are overos.
At one time, the overo
gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...
was thought to be a
dominant gene
In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and ...
, though it was acknowledged that more than one gene seemed to influence overo color, and overo offspring from nonspotted Quarter Horse parents was known.
[Bowling, A.T. "Dominant Inheritance of Overo Spotting in Paint Horses." ''The Journal of Heredity'' 1994:85(3):222-224](_blank)
web site accessed May 25, 2008 However, the full genetic basis for overo patterns is still not fully described.
In the case of most
pinto and some Paint cropouts, another cause is the
sabino gene, which can exhibit its presence with anything from tall white stockings or bold face markings, known as "high white," to significant spotting patterns.
Research indicates that most Sabino patterning is probably
polygenic
A polygene is a member of a group of non- epistatic genes that interact additively to influence a phenotypic trait, thus contributing to multiple-gene inheritance (polygenic inheritance, multigenic inheritance, quantitative inheritance), a type ...
, caused by a
gene complex that is not the same as the gene or gene-complex which creates the overo pattern. One sabino gene, SB1, has been identified, but there appear to be others, as many sabino marked horses do not carry SB1.
APHA site: "Genetic Equation: Sabino"
People seeking to produce color via the Sabino gene have noticed that crossing horses who both exhibit at least minimal sabino traits will usually result in a foal with more "loud" (flashy) coloring.
Usually a cropout will not be a 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 almost always present from birth and does not ...
. Because the tobiano gene is dominant, all tobianos have a least one tobiano parent.
See also
*Equine coat color genetics
Equine coat color genetics determine a horse's coat color. Many colors are possible, but all variations are produced by changes in only a few genes. bay horse, Bay is the most common color of horse, followed by black and chestnut. A change at the ...
*Equine coat color
Horses exhibit a diverse array of coat colors and distinctive horse markings, markings. A specialized vocabulary has evolved to describe them.
While most horses remain the same coat color throughout life, some undergo gradual color changes as th ...
*American Paint Horse
The American Paint Horse is a breed of horse that combines both the conformational characteristics of a western riding, western stock horse with a pinto horse, pinto spotting pattern of white and dark equine coat color, coat colors. Developed f ...
* Appaloosa
*Pinto horse
A pinto horse has a coat color that consists of large patches of white and any other color. Pinto coloration is also called paint, particolored, or in nations that use British English, simply coloured. Pinto horses have been around since short ...
**Sabino horse
file:Sabino-Pinto-Puerto-Rican-Paso-Fino.jpg, A sabino horse with extensive roaning
Sabino describes a distinct pattern of white spotting in horses. In general, Sabino patterning is visually recognized by roaning or irregular edges of horse ma ...
** Overo
*Horse markings
Markings on horses are usually distinctive white areas on an otherwise dark base equine coat color, 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 no ...
References
{{Equine coat colors
Horse coat colors