Tobiano

As Tobiano or dominant Plattenscheckung the most common Scheckungsmuster is referred to in domestic horses.

Word origin

The name comes from the Tobiano South America of the 19th century. A General Tobias led a cavalry division, whose horses were mostly tobiano spotted at the Battle of Buenes Aires against Spain. 6

Appearance

Most piebald horses in Europe are Tobianos. The spots of these horses are sharply defined and have smooth edges. The eyes are usually dunkel.1a

Usually a tobiano has white feet or even more pronounced leg badges. The head badge is not more pronounced than in an otherwise identical predisposed horse without tobiano gene. There are often no badge vorhanden.1a

The white spots in contrast to those of the cross frame Overo usually at least one point the Rückenlinie.1a

A horse with small plates or Tobianoscheckung often has only white leg markings. At slightly more white small spots the direction belly added on the center back, zeigen.1a

A tobiano pinto or plate with lots of white, the last black spots usually on the head. If he has a little more black and the tail ( two-colored tail), down the front at the base of the hind leg ( lumbar region ) and before the Brust.1a

Sometimes, especially in homozygous Tobianos, small spots between the black dots ( Inkspots ) auftreten.1a

At the places where no white spots are, the horse looks like it would be like without the Scheckungsgen. So there are black, bay, foxes, dun, Isabel, Roans with Plattenscheckung.1a

Genetics

The Tobianoscheckung inherited dominant, that is, horses that have the gene twice, look almost exactly like horses that have it only once. It is a milder form of leucism. The white spots occur because not all areas of the skin by the melanocytes ( pigment -forming cells) are populated.

The gene for the spotting is abbreviated to for Tobiano. A mutation, in which a portion in the intron 13 of the kit is untwisted locus, was used as the test gene for Tobiano. Since not carry this mutation at Lewitzer 14% of Tobianos, it can not be the cause of the spotting. Another twisted body is just after the c-kit locus. It is quite possibly the causative mutation because it is associated with all previously studied breeds with the spotting. The spotting is probably caused by that gene regions were cut to determine which serve as often the KIT protein are produced soll.257

The kit gene itself is located on horse chromosome 13 ( ECA13 ) and is at stichelhaarigen horses, the mutated dominant white color of the horse and the Sabinoscheckung. The tobiano mutation is inherited because of the small distance to this gene always together with the healthy KIT gene. If ( the gene therefore has twice) a horse for one of these four genes is homozygous, it can have none of the other two genes. If it is not homozygous, it can have at most two of these investments haben.35

If a horse is both the Overo and the Tobianogen has, it looks mostly like a tobiano aus.4

On the same chromosome near the cKit locus is the extension locus of the horse, so that the predisposition to chestnut color .3 often inherited together with the spotting

Breeds

When Lewitzer the breed standard dictates that they have to be Tobianoschecken.

The Tobianogen is the most common Scheckungsgen. In breeds where spotting is desirable, therefore, a large proportion of the animals on this Scheckungsgen, so the Arabs Pinto, the Paint Horse and Tinker.