Was mich nur wundert ist, dass es keine anderen Highland-Kreuzungstiere zu sehen gibt. Ich meine auf der Seite von Stichting Taurus gelesen zu haben, dass es bereits 2010 Sayaguesa x Highland Kreuzungen und Podolica x Highland Kreuzungen gab. Was ist aus den Tieren geworden? Die müssten ja mittlerweile um die 3 Jahre alt sein und evtl. schon selber Nachwuchs haben. Gibt es dazu auch Bilder? Es wird da auch von 2 Podolicas aus Emryotransfer geredet... Was ist mit denen passiert?
Interessiert mich sehr wie die Aussehen!!!
Gibt es auch Bilder von männlichen Maremmana x Highland Tieren? Die werden ja wohl kaum ALLE weiblich geworden sein, oder?
Zu der Brindle-Farbe:
ich glaube, dass das ein ganz normaler Farbschlag der Highlands ist, der hin und wieder vorkommt, genauso, wie es schwarze Highlands gibt.
Sprich diese Färbung ist von den Highlands "eingeschleppt"
Und ich denke, dass gegen diesen Farbschlag möglichst früh selektiert werden sollte!
While the phenotype is important, the focus of attention is placed on the aurochsen’s genotype, its instincts and its ecological role. Thus the backbreeding of the aurochs will be implemented in three main phases:
Phase 1: Breeding to the phenotype / breeding for quantity
1.a: Compiling a longlist of suitable breeds (~30 were found);
1.b: Selecting a shortlist of breeds to be used for the basic breeding (6 breeds were selected);
1.c: Mass breeding on the basis of as many individuals as possible with controlled and non-controlled crossings (important to create a large gene pool for the tauros and a large breeding base for phase 2).
Phase 2: Breeding to the genotype / breeding for quality
2.a: (Parallel to phase 1) scientific ground work: (I) Determining the DNA of the 30 longlist breeds and of as many aurochsen finds as possible, (II) analysing the ecological role of aurochs and domestic cattle;
2.b: Controlled crossings and selection on basis of the scientific findings.
Phase 3: Natural selection
3.a: “Fine honing” of the genotype through natural selection in the final habitats of the individual herds.
The final phase is the one that bullseye advocated as the main one, and it is the one that will truly turn the tauros into a wild animal that is part of its ecosystem, but only in combination with phases 1 and 2 will it turn the tauros into a backbred wild aurochs (aside from the 3-phase process being much faster than simply relying on natural selection).
1. Selection of breeds
There has been a lot of wishful thinking going on in this thread concerning the breeds that might be used in breeding the tauros. The problem in selecting appropriate breeds is that you have two potentially conflicting aims: (a) inclusion of wanted traits, (b) exclusion of unwanted traits. This may sound self-evident, but the problem is that the more breeds you include the more unwanted traits will end up in your gene pool, and getting rid of those is not as easy as it may seem. (On one web site I saw a pretty recent picture of a piebald Heck calf – after 80–90 years of breeding. That really gives one a feel for the scope of the problem.) So what you want to do is start with as few breeds as possible. This means selecting just a few breeds which have a lot of desirable traits and excluding breeds with just a few positive traits, even if these are spectacular. I trust the Tauros people to have given this some thought and to have selected the most suitable breeds available. (This does not exclude the careful and monitored introgression of further breeds in phase 2.)
There was some discussion about primitive breeds with some zebu genes versus purely taurine but highly domesticated breeds. Primitive taurine would of course be the best, but all northern breeds are phenotypically further removed from the aurochs than the primitive southern breeds (size, colouring, dimorphism, etc.), and as for highly domesticated breeds, you want to keep as far away from them as possible. Here the discussion centred too much on looks and not enough on behaviour as regulated by instinct, hormones, etc.. The problem with highly domesticated breeds is that you usually have a correlating high loss of instincts, which you definitely do not want in the tauros gene pool, and your chances of getting rid of those once you have them are close to nil.
A similar reasoning applies to Spanish fighting cattle, no matter how wonderfully aurochsen-like they might look. These were bred not to flee but to attack in a tight situation and this applies to both sexes. All breeding cows are screened on this trait when young. This constitutes an instinctual warping of the race, and again, one which you definitely do not want.
There was also a bit of discussion about highland cattle. It is true, they are not as perfect as the southern breeds, but they have two advantages nonetheless. Firstly, they give the tauros a broad, healthy genetic base. To achieve the same effect with the southern breeds, you would have to seriously deplete the numbers of those races in their home countries, which is not in the interest of the Tauros Project. Secondly, they will only be used for the central and northern herds, where they add their adaption to the northern climate to the gene pool. From what I have read here and there, Boškarin will be used in southeastern Europe, Maronesa in Portugal and Sayaguesa in Italia (though the two latter are already part of the basic breeds?) to add adaption to the local environment in tauros herds in those countries. And I would assume that local landraces like Kerry cattle in Ireland, Jutland cattle in Denmark, Ringamåla cattle in Sweden, Česká červinka in Czechia, etc. would be used, if ever tauros herds were founded there.
2. Breeding the Tauros
There have been quite a few jubilant comments about the F1 crosses, how aurochs-like they already are, and speculations on which race would be the perfect partner for individual F1 specimens (Manolo Uno especially) to get rid of remaining minor deficiencies. Unfortunately, none of this is true. These misconceptions arise from not differentiating between phenotype and genotype. If anything, the F1 crosses could be said to be a step back from the parental breeds – but a necessary step back. To explain this one needs to look at the differences between three types of breeding generations, the P-generation, the F1-generation and the F2 and following generations. (There was one comment in this thread about this being too simplistic, about having to differentiate exactly between F-generations and B-generations etc. This is only relevant for high precision breeding of races and breeding lines and not applicable to the Tauros Project.)
P: The parental animals are very homogeneous genetically and will pass on this homogeneity to their purebred offspring. A Podolica bred to a Podolica will produce a Podolica. In these animals, the phenotype and the genotype correlate closely.
F1: Genetically the F1 animals are the height of inhomogeneity – but in a very ordered way. All 30 pairs of chromosomes will be made up of one paternal chromosome and one maternal chromosome. Depending on how the alleles of the individual genes interact (dominant/recessive, intermediate, codominant), an F1 animal may have genetic traits which do not show up in the phenotype. Phenotype and genotype no longer correlate, but the hidden genes are known when you know the parental races.
F2 and following: Genetically all chaos breaks lose. Phenotype and genotype do not correlate, and as an F2 animal’s genes are a wild mix of the ancestral genes, the only way to be sure about its genetic makeup would be genetic testing.
A good example to make clear the resulting problems might be horn length. I assume (but do not know) that a simple feature like horn length is governed by only one gene and that the phenotypic showing will be intermediate to the two alleles of the gene. If you cross a Pajuna (too short horns) with a Barrosa (too long horns) the resulting horn length should be perfect – but only phenotypically. Genotypically, the F1 offspring has one gene for too long horns and on for too short horns, and it is one of these imperfect genes that it will pass on to the F2 generation and not its phenotypically perfect horn length.
That is why I called the F1 generation a step back. Manolo Uno, for example, as a Maremmana × Pajuna cross has one complete set of Maremmana chromosomes and one complete set of Pajuna chromosomes. This means that in his genes he has all the desirable traits of both Maremmana and Pajuna, but unfortunately he also has all the undesirable traits of either race. Which alleles he will pass on to his offspring is governed by pure chance.
Thus the importance of Manolo Uno and the other F1 bulls lies not in how they look like now, but in the possibilities they offer for the future. Bred to as many cows as possible pure chance will take over, a lot of their male offspring will be genotypically less valuable then they are, but there will be those who are more valuable: a higher percentage of genes with desirable traits and a lower percentage of genes with undesirable traits. These ‘improved’ bulls can then be used in the same way to breed the next generation of superior bulls, and so on. Only the bulls need be tested, the average genetic quality of the cows will rise with each generation because of the rising genetic quality of the bulls fathering them. (Though controlled breeding, i.e. selecting suitable cows for each bull, should speed up the process.)
There are two requirements for this to happen. One is that you have a large enough base of cows to breed your bulls to. Each breeding act is like a roll of dice, and the more dice you have the higher is your chance of a good roll, i.e. a superior bull.
The second requirement is a high quality screening process. This is where the scientific groundwork will come to fruition. But this is now only very rough guesswork on my part. For many genetic loci the function and the desirable and undesirable alleles will be known. The Tauros people will, I assume, have identified more genetic loci where there is few or no genetic variation in the aurochsen DNA, but where the domestic cattle differ. Here the aurochsen alleles will be the desirable ones. For all these loci, the bulls can be tested genetically, which effectively eliminates the uncertainties of using the phenotype to guess at the genotype.
3. The role of natural selection
Here a word to the general concept of breeding back the aurochs. To opponents of the concept such a thing as “breeding back an extinct species” is impossible. I disagree for three reasons.
1. This has been said often already: Bos primigenius is not extinct, only its subspecies B. p. primigenius is. Most, probably all, of the relevant DNA needed to breed back the aurochs can be found in B. p. tauros. (For a variety of reasons I assume that there will have been a lot of introgression of European aurochs into domestic cattle in ancient times.) And that is what the Tauros Project is all about: collecting the relevant data and reuniting all those scattered aurochs DNA in one animal again.
2. It will not be a 100 % replica of the extinct aurochs, but neither would a contemporary aurochs be, if the breed had survived till today. The holocene aurochsen gene pool differed from the aurochsen gene pool of Germanic times which again differed from the aurochsen gene pool of the middle ages. Evolutionary forces in a radically changing environment would have continued to shape and alter the aurochsen gene pool right up to our times. The purpose of the tauros is not to replicate some outdated stage of aurochsen development, but to be an aurochs for the 21st century. Nature is dynamic, but the thinking of some nature conservationists can sometimes be strangely static and thus, in my opinion, counterproductive.
3. The tauros will not be as perfect a fit in its environment as a naturally evolved aurochs would have been, but that is not a criterion for exclusion. Fitting in your environment is not a matter of ‘yes or no’, it is a matter of degree. This can be seen for example in the relationship of trees and insects. In central Europe, the oaks (Quercus) offer a habitat for 284 species of insects, the hawthorns (Crataegus) for 149, beeches (Fagus) for 64, and linden trees (Tilia) for only 31. This does not mean that environmentally oaks are good trees and linden bad, it just means that oaks have been present in central Europe much longer and accordingly their environmental integration goes much deeper – and as time goes by, it will grow more deeper still. The same goes for the tauros. Wherever it is rewilded (or used in controlled grazing projects) it will step into the extinct aurochsen’s place and become a part of the local environmental processes.
As soon as this happens, phase 3 will start: the natural selection of the tauros. Some few animals will die, especially in the beginning and in areas with harsh winters or a large wolf population, but mostly the selection will be a matter of degree. Those more suited to their environment and those with healthier instincts will have more surviving offspring and as a result the gene pool will slowly shift. And over time, hopefully, ‘cultural’ traits like the creching that bullseye mentioned recently will reappear.
Wenn ich nicht verguckt habe sind bei den Maremmana-Kreuzungen aber mindestens 2 Tudanca-Mischlinge bei... ich würde sie jedenfalls wegen der Hornform als solche einorden...
Anscheinend gibt es also doch mehr als nur die eine Kreuzungskuh
Alles in allem jedenfalls jetzt schon sehr schöne Tiere!
ist sicherlich der Maremmana x Pajuna Stier???Manolo Uno
Ich persönlich würde die Highland-farbenen sowie die schwarzen Kühe aussortieren, und die Kreuzungsstiere dann Kühen zuführen, die guten Dimorphismus vererben und Schlankheit hinzufügen.
ist sicherlich der Maremmana x Pajuna Stier???
Ich denke man muss die schwarzen Kühe (noch) gar nicht aussortieren. Erst wenn das Merkmal nach einer Kreuzung mit Maronesa oder Limia immernoch auftritt, sollte dagegen selektiert werden.
Guter Punkt; letztendlich könnten ja auch bei diesen Kühen gute Merkmale auftreten, die bei den anderen Exemplaren nicht zu finden sind
Guter Punkt; letztendlich könnten ja auch bei diesen Kühen gute Merkmale auftreten, die bei den anderen Exemplaren nicht zu finden sind
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