Skewbald is a coat pattern in which large, irregular patches of white overlie a non-black base color — bay, chestnut, brown, roan, or any other base coat that is not black. When the base is black, the equivalent pattern is called piebald. Both piebald and skewbald fall under the North American pinto category, which groups both patterns together without distinguishing the base color. The British equestrian tradition uses piebald and skewbald consistently to separate the two.
The white patches in a skewbald horse arise from the same white-patterning gene loci — tobiano, frame overo, splashed white, sabino — that produce piebald coloring. The distribution and shape of the patches depend on which gene or combination of genes is active: tobiano tends to produce rounded patches that cross the topline; frame overo leaves the topline dark with white framed by color on the sides; splashed white creates a dipped appearance with blue eyes. Understanding the pattern type matters for predicting what a skewbald’s offspring will look like when crossed with other patterned or solid horses.
Skewbald horses appear across many breeds and are registered by both the Pinto Horse Association of America (by pattern type) and, in some breeds, by breed registries that accept pinto coloring. The color pattern alone does not indicate breed or conformation. For coat color genetics in broader context, see horse coat colors explained.
Splashed white, one of the gene variants that produces skewbald markings, is associated with a distinctive facial pattern and a high frequency of blue eyes; horses with maximum splashed white expression may show some degree of hearing impairment linked to melanocyte absence in the inner ear. Eye conditions in white-marked horses — including uveitis and light sensitivity from reduced periocular pigment — are covered at eye problems in horses. Brindle striping — caused by somatic chimerism rather than white-patterning genes — can overlie any base coat, including skewbald, without being mechanistically related to the spotting loci.
Further Reading
Further reading on pinto patterning and related coat markings: