Strawberry roan

For other uses, see Strawberry Roan (disambiguation).

Strawberry roan, also known as chestnut roan, is a horse coat color characterized by a stable mix of reddish-brown and white hairs, typically with a darker head and lower limbs. Due to its wide range of shades and seasonal variations, the coat has inspired rich poetic terminology, often drawn from botanical language in both English and French.

Strawberry roan horse

Before genetic testing was possible, strawberry roan was identified solely by phenotype. As early as the 1910s, researchers hypothesized a genetic basis, referring to a “Roan factor.” Genetically, this color results from epistasis: the presence of at least one copy of the Roan allele (Rn) acting on a chestnut base coat. The mutation responsible, discovered in 1999, is located on the KIT gene.

Historically, this coat color was noted in two horses brought to the Americas by Hernán Cortés and appears in literature and traditional songs. It can be found in various horse breeds capable of expressing roan on a chestnut base, including the Dartmoor, Breton, Belgian, Quarter Horse, and Criollo.

Terminology

Strawberry roan horse

The term red roan may refer to strawberry roan,^[1][2] but it more commonly denotes bay roan, potentially causing confusion. To avoid ambiguity chestnut roan is often preferred. ^[1][3]

Depending on the shade, strawberry roan horses may also be referred to as lilac roan or honey roan.^[4]

In French

The National Center of Textual and Lexical Resources (CNRTL by its acronym in French) defines aubère (strawberry roan) as "[referring to a horse]: Whose coat is made up of a mixture of white and chestnut hairs".^[5] The term appears in early French sources, such as François-Antoine Pomey's Indiculus Universalis, Georges Guillet de Saint-George's 1678 work,^[6][7] and Gilles Ménage's Dictionnaire Etymologique (1694),^[8][9] as well as in many 19th- and 20th-century dictionaries.^[5] Spelling variants like aubert are noted as incorrect by authors such as Félix Lecoq and Edmond Lavalard.^[10][11]

Historian Michel Pastoureau, in Les Couleurs de nos souvenirs, emphasizes the poetic richness of historical horse coat terminology, citing the aubère coat as an example.^[12] The adjective auberisé (flecked) describes a coat partially displaying this color.^[12][13] Numerous French terms historically described variations of the strawberry roan coat, reflecting its many possible shades. As Baron de Curnieu wrote:^[14][15]

The chestnut roan has been called mille-fleurs (hypericum flower), aubère (strawberry roan), pêchard, fleur de pêcher (peach blossom), etc. The various shades of chestnut, combined with white in various proportions, give rise to a thousand varieties which it is impossible to designate by precise names, but whose particular accidents are easy to describe in the reports.^[15]

Peach blossoms (Prunus persica), whose hue inspired a French name for the color of the horse

The coat is often likened to the Hypericum flower,^[16] with names like pêchard or mille-fleurs evoking its pinkish tones.^[10][17]

Although aubère is now considered archaic,^[1] it was included in the 1999 French coat color classification.^[18] The Institut français du cheval et de l'équitation (IFCE by its acronym in French) officially uses alezan granité to designate the strawberry roan phenotype.^[19][20] To facilitate genetic distinction, the English term alezan roan is sometimes used in French, as aubère can refer to various phenotypes, and rouan typically designates bay roan in French.^[21]

Light strawberry roans are sometimes described as hypericum flower, with distinct white hairs on a reddish background resembling a profusion of small blossoms.^[22][17][23] Interpretations of related terms vary: Merche assigns peach blossom to dark roans,^[22] Lavalard to pinkish ones, and Pastoureau reserves peach blossom for light coats and lilac flower for darker ones.^[17][12] In the 19th century, dealers often applied the term pêchard indiscriminately to both bay and chestnut-based roans.^[22]

In other languages

The strawberry roan coat is known by various names across languages: In Walloon, the strawberry roan coat is called blanc baïet,^[24] in German it is called fuschsschimmel^[12] or rotschimmel,^[25] and in Hungarian it is called fakó.^[26] In Wolof, it is called Jeñ, Jeñ bu weex when white dominates, and Jeñ bu xonq when red dominates.^[27]

History

Head of an American strawberry roan horse

In 1910, Alfred Sturtevant published a study in The Biological Bulletin identifying a genetic factor for the roan coat, which he labeled "R." He observed that roan chestnut coats appeared in less than 10% of carriage horses in New York City but were not classified separately.^[28] In 1912, he asserted that the roan trait involved a mix of white hairs with a base color and appeared to be dominantly inherited.^[29] Edward N. Wentworth, in 1913, recognized both chestnut and black roan horses, suggesting the likely existence of chestnut roan as a distinct coat.^[30]

Building on this research, Sewall Wright (1917) distinguished between gray and roan: a chestnut foal turning white with age belongs to the gray family, while a chestnut foal born roan remains so and belongs to the roan category.^[31]

In 1979, Harold F. Hintz and Lloyd Dale Van Vleck hypothesized that homozygosity for the roan gene could be lethal in utero, based on statistical analysis of roan births.^[32] In 1984, Dr. Dan P. Sponenberg demonstrated epistasis between the roan gene and chestnut base coat after breeding a Belgian bay roan stallion to chestnut mares, resulting in mostly bay roan offspring and only one chestnut roan.^[25][33] In 1999, Stefan Marklund and colleagues located the mutation responsible for all roan phenotypes on exon 19 of the KIT gene,^[34] although the exact causal mutation has yet to be identified.^[2][25]

Description

Strawberry roan pony's head, darker than its body, in Brittany.

Strawberry roan is defined as a stable mixture of reddish (chestnut) and white hairs, varying in proportion.^{[1][35][36][22][37]} Some individuals appear nearly white, while others retain a strong red base.^[38]

The mane and tail may be mixed or solid-colored.^[17] The head and lower limbs are typically darker than the rest of the body.^[39]

Shading ranges from light to dark,^[22] depending on the proportion of white hairs and the shade of the base coat.^[10][17][40] Terminology includes:

• Light strawberry roan: predominantly white hairs;^[22][17][40]
• Dark strawberry roan: predominantly red hairs;^[22][40][17]
• Ordinary strawberry roan: roughly equal mixture;^[22][40][17]

• 
  Dark strawberry roan with few white hairs
• 
  Light strawberry roan with lots of white hairs
• 
  New Forest strawberry roan foal

Corn marks—darker patches from hair regrowth after injury—may also appear.^[41]

• 
• 
• 
• 
• 
• 

Although roan horses experience seasonal color variation (lighter in summer, darker in winter), the overall coat does not change with age as in gray horses.^[42] Roaning in foals can be confirmed by inspecting the white base of the coat; foals are born darker and reach adult coloring around two years of age.^[43]

Visual confusion

Strawberry roan is frequently mistaken for other coat types:^[44]

• Bay roan: Also caused by the Roan (RN) allele but based on a bay coat. The absence of black hairs in strawberry roan (a chestnut base) helps differentiate them.^[22][45]
  • 
    A bay roan, like this Ardennais, has black hairs.
  • 
    A chestnut-based gray, like this Arabian, has a whitening head, becoming whiter and whiter over time.
  • 
    A varnish roan has few manes, streaked hooves and becomes whiter and whiter over time.

• Gray: Chestnut horses undergoing graying can resemble roans.^{[18][46][47][48]} Gray horses show progressive whitening, including on the head, and their coat continues to evolve over time, unlike roans, whose coat remains stable.^[47] Waiting a year reveals whether the number of white hairs increases (gray) or remains constant (roan).^[18]

• Varnish roan: Associated with the leopard complex, varnish roans show specific markers: an inverted V on the face, less abundant mane, striated hooves, and white sclera (eye rims). Their coats also whiten progressively with age.^[1]

Distribution

Strawberry roan Belgian horse

Strawberry roan coats are found in many breeds of horse,^[18][25] although the precise origins and frequency of the trait remain uncertain.^[25]

Historical records mention two strawberry roan horses among those brought to the Americas by Hernán Cortés: to the American Continent; one owned by a man named Moron from Vaimo, and another by Vaena of La Trinidad.^[49][50] Today, the Roan mutation, which underlies this coat, occurs in numerous American breeds, including the Quarter Horse, Criollo, Paso Fino, Peruvian Paso, Mustang, Nokota, and American Miniature Horse.^[1][25][51]

The coat also appears in draft breeds such as the Belgian Trait,^[25] although it is less common than bay roan in these populations.^[33] One notable example is Brooklyn Supreme, a Belgian draft horse believed to be the heaviest horse ever recorded, who had this coat color.^[52] Other draft breeds like the Ardennais can also express roan variants.^[1] Among ponies, strawberry roan appears in Welsh, Dartmoor, and New Forest breeds.^[1]

The coat is nearly absent in sport horses and genetically impossible in Arabians, as the Roan mutation does not exist in that breed.^[1]

Genetics

Strawberry roan results from the interaction (epistasis) between a chestnut base coat and the Roan gene.^[46][25] The trait is inherited in an autosomal dominant manner, meaning only one copy of the Roan allele (symbolized as RN; absence denoted as rn) is needed for expression.^[25][43][2]

The KIT gene, involved in the regulation of pigmentation cells, governs the expression of this trait.^[25] Strawberry roan, like all roan coats, can now be detected through genetic testing.^[25]

Combination with other coat genes

In this miniature horse, the strawberry roan coat is expressed in combination with the flaxen gene, which gives blond tones to the manes.

The Roan trait can be combined with gray, although as with all gray horses, the coat eventually lightens over time and appears white.^[43]

Because the KIT gene also influences other coat patterns, such as tobiano, sabino, and dominant white, horses cannot genetically express both roan and certain pinto traits simultaneously. This is likely due to the gene’s complex behavior and allele interactions.^[43]

Health and pleiotropy

The pleiotropic effects of the RN allele remain poorly understood.^[25] It has long been suspected that the homozygous form (RN/RN) may be lethal in utero, a theory proposed in the late 20th century.^[53][32] However, viable homozygous roan horses have been documented,^[25][43] suggesting that earlier assumptions may have stemmed from phenotypic misidentification or undetected roan expression in genetically roan individuals.^[20] It's also possible that more than one mutation could eventually be linked to the phenotype.^[53]

Cultural references

Japanese yabusame horse

Strawberry roan horses appear in various artistic and folkloric traditions:

• The Jesuit painter Giuseppe Castiglione (Lang Shining) described one of his equine subjects as a "white strawberry roan horse adapted for mountain walking" (Manchu: kulkuri suru; Mongolian: riditu čayan.^[54]
• In Malian Fulani epic poetry, a long-maned strawberry roan horse is attributed to a hero from Djelgôdji (1705–1827).^[54]

• The traditional Mongolian song zaalxan sarga (TGS 126 A6) translates to The Little Strawberry Roan Horse.^[55]
• In Khakass epic poetry, Vladimir Tannagašev described "Khan-Mergen's dark strawberry roan horse of forty fathoms" (Kyryk kulaš synnyg kara sar'attyg Kan-Mergen).^[56]

• In the United States, the most famous western ballad about a bucking horse is The Strawberry Roan,^[57] originally titled The Outlaw Broncho (1915), written by Curley Fletcher (1892–1954).^[57]

Beliefs

Historical beliefs about coat color often attributed character or physical traits to horses.

In Les Arts de l'homme d'épée (1678), Georges Guillet de Saint-George described strawberry roan horses as lacking sensitivity in the mouth and flanks, and noted a supposed tendency toward blindness—traits that lowered their esteem.^[6][7] Baron Charles-Louis-Adélaïde-Henri Mathevon de Curnieu (1811–1871), a 19th-century professor of equestrian science at the Haras national du Pin,^[58] ranked strawberry roan among the least desirable of the "roan" colors, a category in which he included several non-roan shades such as grullo and buckskin.^[22]

In Yakut shamanic traditions, horse coat colors were linked to sacrificial rituals. Ethnologist Wenceslas Sieroszewski recorded that spirit Dohsoun-douïah was appeased with the offering of a golden strawberry roan mare with a white head. Malevolent southern sky spirits required sacrifice of light strawberry roan horses with half-white muzzles, pink nostrils, and white eyes.^[59]

See also

• Equine coat color
• Roan (horse)
• Chestnut (horse color)
• Brooklyn Supreme