Is Sayaguesa the ultimate "breeding-back" breed?

Sayaguesa is used in all three major “breeding-back” projects (Taurus cattle, Tauros cattle and Auerrind cattle) and the influence of the breed in the Lippeaue for example is over 50% on average. Sayaguesa is used that commonly because it simply produced qualitative results from the “breeding-back” perspective. Can we even go so far to say that it is the ultimate “breeding-back” breed? Let’s analyse this.

At first I go over the positive traits of this beautiful breed and what makes them valuable for “breeding-back”, then I have a look at the downsides of Sayaguesa and form a conclusion.

 

The useful traits of Sayaguesa are:

 

-) Sayaguesa can grow very large

 

Some Sayaguesa bulls reach 170 cm at withers height. Dona-Urraca, the Sayaguesa cow that produced a lot of great individuals in the Lippeaue, was very large as well. I stood next to her in 2013 and she must have at least 155 cm tall, probably larger. Sayaguesa is a large breed in general, only slightly smaller than the average of Chianina. Considering that many other very aurochs-like breeds, like Pajuna, Maronesa or Lidia, are on the smaller side, that is very valuable.

 

-) Sayaguesa have an aurochs-like morphology

 

Sayaguesa have a great morphology, with a very large hump and long legs. I have not yet seen a complete Sayaguesa skeleton, but I suspect the processus spinosi are as tall as in the aurochs in many individuals. That’s a not very common trait even among less-derived breeds.

 

-) The horn curvature is useful to very useful in many individuals

 

It is true that many Sayaguesa cows have the horn tips curving outwards, but only after a clear inwards-curve and the horns always face forwards. While the lateral horn orientation is not rarely too low in the breed, some have a perfect primigenius spiral. This is rare in most breeds, and therefore again very valuable.

 

-) They have no domestic colour dilution alleles

 

The “colour genes” of Sayaguesa must be identical to that of the aurochs, as they have no apparent domestic mutations like roan, melanism, erythrism, colour dilutions et cetera. An exception are individuals that have white spots. The dimorphism is something I regard as a different story, because it likely has a different genetic make-up rather than simple “colour genes”.

 

-) They have an elongate skull

 

Sayaguesa have a very aurochs-like skull. In the Lippeaue I once saw the skull of a Sayaguesa cow and it looked virtually identical to that of the Sassenberg cow. The skull is elongate, the snout straight or slightly concave and the orbital bosses well-developed (in the cows, the difference between wild and domestic are more recognizable in the bulls in this trait).

 

Now let’s look at the downsides:

 

-) The sexual dichromatism is almost completely absent

 

Sayaguesa cows are basically bull-coloured with a brownish tint, or very dark brown. That means that the sexual dichromatism is almost completely absent or very reduced. Some Alistana-Sanabresa-influenced Sayaguesa cows have the “right” colour in being reddish brown, but bulls from the same herds may have a saddle.

 

-) The horns are not very large

 

Most Spanish breeds do not have large or huge horns, and Sayaguesa is no exception. While the horns would probably fit Holocene aurochs specimen such as the Himmelev or Prejlerup aurochs in volume, they certainly need more size to match aurochs that had not been influenced by human influences such as hunting and hybridization with cattle.

 

So we see that Sayaguesa has way more positive than negative traits in terms of usefulness for “breeding-back”, and its positive traits are often are very valuable because they are rare among aurochs-like breeds. There are some more negative traits such as a long dewlap or the enlarged intestinum, but including them here would not be useful as these traits also apply to 90% of taurine breeds or more.

My conclusion therefore is: Yes, I think Sayaguesa is currently the most useful breed to be used in “breeding-back” that is not the result of a “breeding-back” project itself. And all current projects rely on this breed to a large extent, which is very positive. The results also speak for themselves – Sayaguesa is a great breed for “breeding-back”.

 

And because it is always fun to dream about more breeding projects, here my idea for a Sayaguesa-project that tries to breed out the few negative traits of Sayaguesa and at the same time keeping the number of new undesired traits as low as possible:

 

First two to four generations: ((Sayaguesa x Watussi) F2 x Sayaguesa) F2

 

Sayaguesa x Maronesa F2

 

Sayaguesa x Lidia F2

 

Sayaguesa x Chianina F2

 

Sixth generation:

 

(Sayaguesa-Watussi crosses x Sayaguesa-Maronesa crosses) x F2

 

(Sayaguesa-Lidia crosses x Sayaguesa-Chianina crosses) x F2

 

Eights generation:

 

Both lineages combined and an F2 from that.