THHNTobiano.pdf

HORSE COLOR

Lesli Kathman, 4700 Lone Tree Ct., Charlotte, NC 28269 <leslikathman@earthlink.net>

Pinto Patterns

Tobianos are probably the most familiar of the pintos for a lot of

people. They are perennial favorites for children's ponies, parade

horses, and stars of television and movie westerns (despite years of

exposure to my obsession with horse color, I still have not broken my

own father of calling them "Tonto-horse-colored"). They remain

popular today in both the real horse world and in our own miniatures.

What Tobianos Look Like

Tobianos look like white horses that have dark spots with smooth

edges. Their face markings tend to be conservative - much like those

found on solid horses - and the eyes are dark. Tobianos almost

always have four white legs and the white on their body will cross over

their necks, back or croup. The borders of the spots themselves are

rounded and well defined, though the placement of many spots in one

area can make the white areas appear jagged. With a tobiano,

however, the key trait is the shape of the dark areas. Even in the most

wildly marked tobiano, it is usually possible to see how roundish spots

"grew together" to form the pattern ( Figure 1 ).

This gelding might be mistaken for a solid horse, if it weren’t for the small line

of white on his hindquarter and the patch on his neck. From his other side,

where there is no white on his body, he looks like an ordinary solid horse.

Tobianos with this little white are rare in most breeds.

Pattern Progression

In the most minimally marked tobianos, what is generally seen

are high stockings that appear to come to a point along the side of the

leg. This is different from the stockings found on sabinos, where the

trailing edge tends to run up the front of the leg. There will typically be

a small patch of white on either the neck or the withers. There may

also be a small amount of white on the croup or at the base of the tail

(which will turn the tail white, or at least partially white). In horses with

a little more patterning, the area along the neck will spread down the

topline, eventually joining with the white on the croup or tail. After this,

the white tends to flow down from the top line towards the white on

the legs, until the individual spots become more obvious.

When a tobiano pattern is about 60% white, it begins to take on

the appearance of the "classic" tobiano with the dark head, chest and

large spots on the flanks or hindquarters. This seems to be the

genetic norm that this pattern gravitates towards, as most tobianos

are marked this way.

When the pattern becomes more extreme, the body spots tend to

be smaller and less numerous, until all that is left dark is the head and

possibly a small area on the chest or hindquarters. It is likely that this

is the most extreme expression of this gene, and that it is as far as the

pattern will progress. Those horses which would qualify as Medicine

Hats (those with less color on their heads) are most likely the product

of overo genes in addition to the tobiano gene.

How the Tobiano (T) Gene Works

Figure 1. These two tobianos show how the circular spots have merged to

create the pattern. Note that they are not actually perfect circles.

The tobiano pattern is the result of a dominant gene, so any

horse that inherits it will be a tobiano. This also means that all

tobianos have at least one tobiano parent, who had at least one least

one tobiano parent, who themselves had a tobiano parent - creating

an unbroken line of tobiano ancestors. Horses that carry one gene for

tobiano (heterozygous) will produce tobiano offspring 50% of the time

when bred to solid mates. If the horse is homozygous for tobiano

(carrying two tobiano genes), then all that horse's offspring will be

tobianos. This fact has made tobianos extremely popular in pinto

breeding programs, because a homozygous horse will breed "true" for

the color regardless of the color of the other parent. To date, there

have been no proven cases of 100% color-producing overos.

For a horse to be a homozygous tobiano, it must have two

tobiano parents. It is possible to identify a homozygous tobiano

without knowing the horse's parentage, though, thanks to a genetic

test developed by UC Davis that can confirm that the horse is indeed

carrying two copies of the gene. Many breeders test their tobiano

stallions for homozygosity because mare owners like knowing there is

no doubt that the resulting foal will be a pinto. Even without a test,

homozygotes can often be identified by small, disconnected spots

known as cat tracks. These spots vary, with some individuals

displaying only a few while others are so densely speckled with them

as to appear partially leopard-patterned, but they are found on most

homozygous tobianos.

Colors That Can Be Confused with Tobiano

As a group, tobianos do not tend to show as much individual

variation as the overo patterns. The majority of tobianos will fall into a

fairly typical expression of the gene that will include a dark head, dark

chest, and large spots (or grouping of spots) along the flanks and

hindquarters. This consistent "look" makes this the easiest pinto

pattern to identify. While it is not unusual to have some questions

about which overo gene a horse carries when the horse displays only

a small amount of white, or is predominantly white, in most cases the

presence of the tobiano gene is pretty obvious. This is probably why

many registries simply classify patterned horses as either tobiano or

overo: essentially, tobiano or "not tobiano".

Nonetheless, there are occasional individuals whose patterns are

less typical, which may lead to the horse being misidentified.

Occasionally tobianos are seen with so little white along the

topline that they appear to be solid, though most will have at least a

small amount of white in the mane, along the croup or at the base of

the tail. What will differentiate these horses from minimally marked

overos are their conservative face markings in relation to the high

white seen on the legs. The other misleading trait that is seen in rare

instances is dark legs. While one or two dark legs are certainly not

typical of the pattern, they are occasionally seen in minimally marked

horses of the Icelandic, Shetland and Miniature breeds. To date, all

the cases I have seen were in those breeds, and it was always the

forelegs that were dark. In most cases, these will be those individuals

with extremely minimal patterns, but I have seen one individual where

the placement of the pattern "slipped", resulting in white that would

normally appear across her topline to be seen along one side of her

body. Oddly enough, the white that would have appeared on the legs

of that same side was missing, as if it had also "slipped" down past

These two Paints have the stereotypical look that most associate with the

tobiano pattern: dark head, chest, and flanks.

her legs, while she had rather normal tobiano marking on her off side

legs. She did, however, produce as any other tobiano would, with

approximately half her offspring (from solid stallions) ending up as

rather ordinary looking tobianos.

Breeds That Come in Tobiano

These small spots are called “cat tracks” and usually indicate that the horse is

homozygous for tobiano. The tendency towards really dramatic cat tracks

can run in families.

Because tobiano does not usually take the form of minimal

patterning that can be mistaken for flashy markings, when it is present

in a breed it is usually well known and easy to document. There are

still those breeds where it is not particularly favored, but it does not

"crop-out" in those breeds that have specifically selected against pinto

patterns the way the overo genes do. The tobiano patterns are

widespread across a wide variety of breeds and body types.

In this country it is, of course, found in Paints, though many Paint

breeders complain of a bias against tobianos in the halter classes.

Tobianos do tend to dominate the Paint racing world though. Tobianos

are also found in most of the Southern gaited breeds, including

Saddlebreds, Walking Horses and Missouri Fox Trotters. For many

years the tobiano stallion Chubasco dominated the Saddle & BridIe

sire list, and did much to popularize the color in Saddlebreds. In

Walking horses, there is at least one line for this color that goes back

to the early stud books, but nonetheless tobianos are still viewed by

many breeders as "impure" or "tainted". This long-standing prejudice

is part of what lead to the formation of the Spotted Saddle Horse

registries in the mid-1980s. This bias has been changing in recent

years, however, with the growing popularity of colorful horses,

particularly in the flat-shod classes.

Some of the reasoning behind this bias may be that in this

country the color has most often been associated with ponies. Indeed,

a large number of grade children's ponies are tobiano spotted. Among

registered ponies, however, the color is far less common. Of the

British Native ponies, only the Shetland allows tobianos, while in this

country it is the American Shetlands, Miniatures and Chicoteagues.

Icelandics also have the tobiano gene, and may well be the source for

the color in the Shetlands, since they are believed to be the older

breed. At one time there were tobiano Hackneys, but the lines were

lost sometime in the early 1900s.

In recent years, the color has been seen in Drafters thanks to the

formation of the North American Spotted Draft Horse Association.

While both overos and tobianos are registered, the first horse

registered was the black and white tobiano Percheron-cross Pecos

Chief, and it would seem that black and white tobianos remain

extremely popular within that breed. There was also a line of tobiano

Shires in the mid- to late-1800s, but like the Hackneys this was later

lost, perhaps another casualty of that era's dislike of the gypsies. It

was, after all, the gypsies who were so well known for their colorful

horses, particularly heavy horses. In more recent years these horses,

which are quite often tobiano-marked, have been marketed in this

country as Gypsy Vanners. While not called specifically called "gypsy

vanners", we certainly saw many unregistered tobiano drafters while

visiting the British Isles four years ago.

The color is also found in some of the sport horse breeds, largely

due to the popularity of stallions like Samber and Art Deco. In most

cases, the color is coming from Dutch-bred horses, which likely

inherited the pattern from the nearly-extinct Groningen. There is also

a notation in Bonnie Hendricks' excellent book International

Encyclopedia of Horse Breeds that there is a line of spotted

Trakehners, accompanied by a photograph of a tobiano mare.

Within the Spanish breeds, the pattern is found in the Paso Fino

and in American mustangs. I have also personally seen pictures of

Andalusians bullfighting in Spain that were tobianos, though I would

suspect they were unregistered and may not have been purebred. By

looking at old paintings, it is clear that the Iberian horse did

at one time come in tobiano.

not be able to explain the exact reason, inaccurate patterns will look

somehow "wrong". Few things will help your paint jobs like a thorough

understanding of how the patterns progress, and the small details that

typify the various patterns. That said, there are some consistent

problems that show up in models painted to represent the tobiano

pattern which are pretty easy to avoid when the pattern is better

understood.

The most common problem that I see on tobiano models is that

the entire outline of a group of spots is rounded, instead of just the

individual spot. This gives the area a "blobby" look, rather than the

appearance of roundish spots that have overlapped as they grew

together. This problem is easy to correct by painting over the blobs to

have better definition to where the spots connect ( Figure 2 ).

On the flip side, in more recent years many artists have taken the

concept of interconnected spots to an unrealistic extreme. While it is

true that the pattern does give the appearance of "round spots that

have grown together", it should be remembered that those spots are

not exactly round, and that their intersections with one another are not

precisely defined in all instances. In the same category are those

horses with many smaller spots that almost or only slightly overlap.

While large numbers of elaborate interconnecting spots are visually

interesting due to the play of positive and negative space, in many

cases these models are far more artistically appealing than they are

accurate or realistic. While basically roundish in shape and clean-

edged, tobiano spots are not completely round or completely smooth,

and they tend to overlap quite a bit (refer again to Figure 1 for a good

example of just how much these spots tend to overlap). The spots

also have a tendency to follow the direction of hair growth, or at least

not to deviate strongly from it.

Painting Tobianos

The real challenge to pintos is not the actual painting, but rather

getting correct, accurate patterns. While the inexperienced eye may

A lot of facial white on an otherwise tobiano-patterned horse (above)

unusually indicates that the horse is also carrying one of the overo genes in

addition to the tobiano gene. Horses that are homozygous for tobiano do not

inherit any more white - on the face or otherwise - than other tobianos..

The other mistake, though less common now than it once was, is to

have alternating areas of light and dark in the mane that do not

correspond with the pattern. Mane color is determined by the coat

color along the crest of the neck; white mane will grow from the white

areas, and dark mane will grow from the dark areas. While some odd-

colored hairs can appear without any visible color on the neck

because there is a small light or dark spot on the skin right where the

mane grows, large amounts of light or dark growing from the opposite

Figure 2. A. Here are the outlines of the interconnected spots, while B. shows

how such a marking should appear on the horse. If the entire area were

loosely outlined with curved lines, it would look like C., which is unrealistic.

colored neck will look unrealistic. Finally, tobianos do typically have

conservative face markings; stars, snips, strips and ordinary blazes. It

would appear that even the whitest tobianos still keep their solid

faces. Horses that have extensive white on the face, or dark areas

that only partially cover the head or ears (medicine hats), probably

carry one of the overo genes in addition to the one for tobiano. When

painting a model like this, care needs to be taken that the breed being

portrayed also comes in overo, or such a horse would likely never

exist.

Like any other color or pattern, studying as many examples as

possible, and referring to reference photos or clippings when painting

will help avoid most realism problems. For those that do not have

regular access to tobiano horses, The Paint Horse Journal (PO Box

961023, Fort Worth, TX 76161) comes out monthly and averages

more than 300 pages in an issue, and is a great reference for all the

pinto patterns.

In the next issue, we will switch gears from one of the most

widespread pinto patterns to one of the rarest - frame overo! The

overo patterns happen to be my area of interest, so I look forward to

future issues where we will look at each of them.

on horse color that originally appeared in The Hobby Horse News, a

magazine for the model horse collecting community that is no longer

published. The articles may be copied for personal, non-commercial use.

Individuals may also offer the files for downloading provided they are properly

attributed, but inclusion in commercial publications (magazines, newsletters,

books) is forbidden unless written permission is obtained from the author.

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