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6. PAINTS AND PINTOS: TOBIANO, OVERO, TOVERO, SABINO, MEDICINE HAT
The two most common paint patterns are tobiano and overo. They are controlled by genes at different loci, so it is possible to get a horse who is both tobiano and overo -- a tovero.
"is apparently dominant and is characterized by white over the back and up the legs, and by a normally marked head."
"apparently requires a pair of recessive genes and is characterized by color over the back and on the legs and by much white on the head."
Dan Duval clarifies:
Generally, overo is a colored horse with some white while a tobiano is a white horse with some color. But don't count on this, since some lines (such as Far Ute Keno and his progeny) are overo, but display more white than color, and I know of tobiano lines which are covered in color.
To be specific, overos tend to have color along the length of the spine between the withers and the top of the croup. They also tend to have color on all four legs (though not always.) Blue eyes (or wall-eyed) are an overo trait exclusively. Overos often have one or more white hooves (but again, don't count on it.) The color on overos tend to have an irregular border (sort of like a map of Norway) and irregular shapes. The color on overos are often "bordered", where colored hairs and white hairs are mixed in a region 3-10mm around the edge of the colored spots.
Tobianos most often have white crossing the spine. The legs are mostly white (usually only one or two will have color and this mostly at the top.) Tobianos do not have blue eyes (though toveros might.) [Tobianos tend to have "ordinary" looking heads, colored with maybe a star or stripe, in contrast to overos which tend to have very white, "exotic" heads.] Tobianos usually have all-black hooves (but again, don't depend upon this.) Tobiano colors tend to be roughly regular shapes with clean, sharp borders (no bordering, no "maps of Norway"). I don't recall seeing a palomino tobiano, but I suppose they are possible.
The final classification is tovero. These are overo-tobiano mixes and -- boy -- do they cause classification problems. They have characteristics of both strains.
Overo and tobiano are distinct genetic types -- different genes express the characteristics, rather than different selections within the same genes.
Now an easy way to remember the difference in Paint color: OVERO: never white OVER the back. Never-over. TOBIANO: white goes over the back. tobiano="top albino".
Kind of like imagine a brown horse. Pour paint over his back and let it run down the sides and legs. TOBIANO Now turn him on his back and pour paint on his belly and let it run toward his back. OVERO
SABINO is a different white pattern, controlled by a completely different gene than either tobiano or overo. Sabinos tend to have completely white legs and big blazes. (Think of those Clydesdales with their big white stockings.) A sabino with a medium amount of white has white legs, an apron face, and white extending up onto the body from the belly. The white patches on the body are very ragged and flecked-looking. A very white sabino can be almost completely white, often with color left only on the ears, chest, and maybe on the flank and dock of the tail. Sabino is common in Clydesdales, where it is erroneously called "roan".
SPLASHED WHITE is yet another white pattern, controlled by yet another gene. Like sabino, these horses usually have white legs, bellies, and faces. Large white patches extend up onto the body from underneath. Unlike sabino, the white patches have clean, non-ragged borders. This pattern occurs in some European breeds.
MEDICINE HAT is a horse that is mostly white but with colored ears (a "war bonnet") and often colored eye rings. They can also have "shields" of color on the chest, flank and along the topline. These horses were thought to have supernatural powers by some Native American tribes. This color pattern can occur in very white paint horses of various genetic backgrounds, particularly overo, tovero, and sabino.
Genetic questions, answered by Tracy
1) overo x tobiano -- what will foal be?
In such a case one would need to know the colors of their parents in order to find out whether the tobiano possibly harbored an overo gene. If not, then a paint offspring would likely be tobiano; a solid-colored offspring is also a possibility. Either way the foal would be an overo carrier, and when bred to an overo could produce overo foals in the next generation.
2) Grey-looking appy filly (may be grey or roan) x few spot leopard stud -- what are chances of nice appy foals?
If she is a roan with spots she will definitely throw appys, including a fifty percent chance for a few spot appy. If she is a grey then you probably have only a fifty percent chance for a true non-greying appy and a fifty percent chance for another grey.
3) Leopard colt -- worth buying? I also have a chance to buy a leopard colt, have not seen him yet, out of a leopard stud, and solid bay mare. Do you think he would throw color or forget him. His sire's pedigree is unknown, dam's side is pretty much solids, chestnuts, bays, roans.. Any help would be appreciated.
If the leopard colt is brightly patterned and non-greying then he will throw color about 50 % of the time when bred to non-appys and 75% of the time when bred to other brightly colored appys. Keep in mind conformation is as important as color. If he is a few spot Appaloosa then he will throw color 100% of the time, although this is unlikely unless his dam is also an appy.
4) Breeding Appy/Warmblood cross for color?
Yes, breeding a few spot Appaloosa to a warmblood would pretty much guarantee a bright Appy type coat pattern. An interesting note, the Appaloosa color pattern used to be a favored one for harness horses, especially warmbloods in Europe, Dalmation dogs were bred to match the Appys. Also I have seen a photograph of a Lippizaner/Appy cross who was 1989 USDF Horse of the Year at Grand Prix. Wonderful mover, noted as having the best piaffe and passage of any horse the judges who judged him had seen, but he was kind of ugly, with a big Lippizaner head and pink skin with a few dark skin spots under his white coat. You see he was a grey. So when you breed your Appy/Warmblood cross choose a non-grey for the Warmblood part, that way the pattern will not grey out.