Rabicano, also called white ticking, is a horse coat color characterized by limited roaning in a specific pattern: interspersed white hairs most dense and originating from the flank and the tailhead. Rabicano is distinct from true roan, which causes evenly-interspersed white hairs throughout the body, except the head and legs.
The word "rabicano" is of Spanish origin - rabo meaning "tail" and cano meaning "white" - thus, it described a horse with white hairs in its tail.  This definition is consistent with the modern usage.
The word appears very early in epic poems in Italian literature: Argalia, a character in Orlando Innamorato (1495), rides a horse named "Rabicano". So too does Astolfo. In Italian, the term simply means "roan" and might therefore have been a descriptive name.
The characteristics most often associated with the rabicano pattern are white hairs at the tailhead and the flank, where the body of the horse is joined by the hindquarters. Like other patterns and colors, the expression of the rabicano trait varies. Most of the factors affecting these variations are unknown, however, it is known that horses with a chestnut or chestnut-based coat express white patterns such as rabicano more readily; that is, they tend to have more white. Minimal expression includes a few white hairs in those areas.
The original definition of "rabicano" refers to the presence of white hairs in the base of the tail, a characteristic called a "skunk" or coon tail. The term "coon tail" is associated with white hairs in the form of rings at the tailhead, while the other terms do not necessarily imply rings. The sides of the tail at the tailhead may have much white hair.
Higher expression of the rabicano pattern on the flanks may produce a coat easy to mistake for true roan. However, in highly-expressed rabicanos, the distribution of white hairs along the barrel may produce faint striping or stippling over the ribs, which is not seen in true roans. Furthermore, the skin of rabicanos may be slightly mottled with pink, particularly on the abdomen and groin. This trait is not seen in true roans, and suggests that like the white hairs associated with other white markings and patterns, the white hairs of a rabicano may be rooted in unpigmented skin cells. However, the genetic and developmental controls of such roaning is presently poorly understood, and has not yet be formally studied.
Prevalence and inheritence
The rabicano pattern is thought to be a dominant gene, however other forms of white ticking not following the rabicano pattern may exist and be controlled by separate mechanisms. Rabicano is present even in breeds which do not possess any true roan individuals, such as Thoroughbreds and Arabian horses.
Rabicano vs. Roan
Rabicano is a white pattern that falls into the category of roaning or scattered white hairs, the genetics of which are not yet fully understood. Sometimes called ticking, rabicano is common even in breeds that do not have true or classic roan, including Arabians and Thoroughbreds. This pattern usually takes the form of scattered white hairs around the junction of the stifle and flank, and peculiar rings of white hairs near the base of the tail. This trait is called a coon tail or skunk tail. Extensively-marked rabicanos sometimes exhibit striations in their pattern on the ribs, giving them a striped appearance. While rabicano itself does not produce white markings on the face and legs, it is often associated with any of the numerous sabino patterns, many of which have been mapped to the KIT gene. Other color patterns mapped to KIT include extension, tobiano, and true roan.This may explain the close association between rabicano and sabino, which are often observed in the same horse.
Rabicanos are not true roans and can be distinguished from true roans by the following:
- Roaning on rabicanos is centralized at the junction of the stifle and the flank; true roan is evenly distributed over the whole body except the points.
- Rabicanos usually have skunk tails or rings of white hairs in the tail, while true roans do not.
- Rabicano roaning often spreads, while true roans usually become darker.
- Rabicanos do not develop corn marks when their skin is damaged.
Rabicano may occur on any base color and may occur in conjunction with any other white pattern, including true roan or gray.
- ↑ Price, Steven D.; Jessie Shiers, William Steinkraus (2007). The Lyons Press Horseman's Dictionary: Full Explanations of More than 2,000 Terms and Phrases Used by Horsemen. Don Burt. Globe Pequot. p. 175. ISBN 1599210363. "rabicano: A coat color in which a few, scattered white hairs appear amid a darker-colored background, usually on the hindquarters and dock"
- ↑ Juan de la Cruz Puig. Antologia de Poetas Argentinos,1910. pg. 131. "Rabicano: caballo que tiene cerdas blancas á la raíz de la cola." [Rabicano: a horse that has white hairs at the root of the tail]
- ↑ Behning, Laura. "Rabicano, Roan, Flaxen, and Frame Overo Morgan Horses". Morgan Colors. http://www.morgancolors.com/othercolors.htm. Retrieved 2008-08-03.
- ↑ B. Kostelnik. "Rabicano". The Horse Colors Site. Hippo-Logistics. http://www.horsecolor.com/white_mixed/roan/rabicano.htm. Retrieved 2008-08-03.
- ↑ "Introduction to Coat Color Genetics". UC Davis. http://www.vgl.ucdavis.edu/services/coatcolor.php. Retrieved 2008-08-03. "The inheritance of scattered white hairs, sometimes called roaning, is not defined."
- ↑ 6.0 6.1 Sponenberg, Dan Phillip (2003-04-11) [1996-01-15]. "4/Patterns of White Occurring on Base Colors". Equine Coat Color Genetics (2 ed.). Wiley-Blackwell. p. 215. ISBN 978-0813807591.
- ↑ Veterinary Genetics Laboratory. "Introduction to Coat Color Genetics". The Regents of the University of California. http://www.vgl.ucdavis.edu/services/coatcolor.php. Retrieved 2008-06-04.
- ↑ Overton, Rebecca (2004-12-15). "In The Genes" (PDF). Quarter Horse News (American Quarter Horse Association): pp. 24–6. http://www.hancockhorses.com/article-roanQHNews.pdf. Retrieved 2008-06-04.
- ↑ Peters, Anne (2002-05-04). "A roan by any other name is a roan". Thoroughbred Times (Lexington: Thoroughbred Times Co. Inc.). http://www.thoroughbredtimes.com/weekly-feature-articles/2002/May/04/A-roan-by-any-other-name-is-a-roan.aspx. Retrieved 2008-06-04.
- ↑ Marklund, S; M Moller, K Sandberg, L Andersson (1999). "Close association between sequence polymorphism in the KIT gene and the roan coat color in horses". Mammalian Genome 10 (3): 283–288. doi:10.1007/s003359900987. PMID 10051325.
- ↑ brooks, SA; TL Lear, DL Adelson, E Bailey (2007). "A chromosome inversion near the KIT gene and the Tobiano spotting pattern in horses". Cytogenetics and Genome Research 119 (3-4): 225–230. doi:10.1159/000112065. PMID 18253033.
- ↑ Andersson, L; K Sandberg (March 1982). "A linkage group composed of three coat color genes and three serum protein loci in horses". Journal of Heredity 73 (2): 91–4. PMID 7096983.