Hardy Oelke (author and Researcher) Germany
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The Kiger Mustang has enjoyed unparalleled popularity as a Spanish-type mustang, and has been the envy of owners and breeders of mustangs stemming from other Herd Management Areas, or registries. As a natural reaction, some of the latter have tried to run down the Kiger, finding fault with this and that of its history.
According to my own investigations, the Kiger's history is second to none, regarding a probable Iberian ancestry. As no American mustang is a native North American animal, it is of no consequence if the nucleus of the Kiger herd came from several of Oregon's wild herds. If the Kiger Mustangs--or any other mustang herd--were transplanted to another area, they wouldn't commence to become different horses there, and they would still have the same ancestry.
Comparing the Kiger's phenotype with that of other mustangs of alleged Spanished ancestry, there is as high a percentage of horses of good Spanish type among the Kigers as there is among any other mustang herd, or population.
If phenotype and general history (all mustangs going back to Spanish horses and all having been exposed to a certain amount of "contamination") aren't enough, we are fortunate today to have scientific methods to ascertain a horse's genotype. Much fuss has been made within the "mustang community" about the bloodtyping of horses; however, that method cannot ascertain a horse's phylogenetics, i.e. a horse's long-term ancestry, what it is derived from. Bloodtyping can ascertain a horse's sire and dam, albeit not very reliably, but not whether a horse goes back to, for instance, Iberian stock. The only reliable method to do that is the sequencing of mitochondrial DNA (mtDNA), which is widely accepted in the scientific world.
If we focus on mtDNA, it is important to note that mtDNA types were established which are geographically linked. Not all existing genotypes could be linked geographically, but among those that were are two for North European ponies, one for Mongolian wild horse (or Przewalski's horse), two for Iberian horses and one for the Sorraia horse. The majority of the Iberian horses were of one genotype (D1). That same genotype was also found in Barb horses, meaning that theses Iberians and the Barb share a common ancestry. Another genotype (A3) was found in a considerable number of Lusitano horses (and in a few Andalusians). This indicates a different origin for the Lusitano.
The Lusitano breed of Portugal and the Andalusian breed of Spain used to be one and the same breed for many centuries, and were only recently divided into separate registries. It is no surprise, therefore, that most Lusitanos have the same genotype as the Andalusian (Pura Raza Espanola), because Spain is so much larger than Portugal, Spanish horses outnumbered thoses of the Portuguese by far, and the influence of Spanish horses on Portugal's was strong. However, the different genotype of a considerable number of Lusitanos indicates that, originally, the Lusitano was built on different stock.
The Sorraia's genotype consists of two mtDNA types, A1 and JS041, both closely related. It's noteworthy that the genetical distance between the Lusitano's genotype (A3) and the JS041 of the Sorraia is not any larger than between the two Sorraia mtDNA patterns (JS041 and A1). However, there is no indication that A3 had evolved out of JS041. And so far, not a single Lusitano or Andalusian has been found with the Sorraia genotype.
Going back to the Kigers: Not surprisingly, our mtDNA tests results show that most Kigers have the Iberian/Barb genotype, which is also found in most other mustangs of Spanish type. This clearly shows that the Kigers are of Spanish ancestry. It also shows the Kiger's relationship to other Spanish mustangs, such as the Sulphurs, or many SMR horses--there is a common ancestry of all these horses.
Interestingly, quite a few Kigers have the "Lusitano genotype" (A3), and many registered with the Sorraia Mustang Studbook are of a phenotype similar to the Lusitano (which is also largely that of the Sorraia). Why that is, one can only speculate, as in contrast to South America, the Portuguese played no role in the conquest of North America. A minority of Spanish horses (Andalusians) are of the A3 genotype, so theoretically, some such horses could have played a dominate role in the heritage of Oregon's mustangs. Anyway, the Kigers are the only mustang population so far with individuals of this genotype.
In summary, we have phylogenetic evidence for an Iberian ancestry of the Kiger Mustang.