Ever since
I came to know of all those aurochs-like cattle, I tried to figure out a way
how to objectively ascertain which breeds are closer to the aurochs than
others. It turned out to be pretty difficult, or nearly impossible.
The
reference for the comparison is the Near Eastern and European Aurochs that was
the ancestor of taurine cattle and also the goal of the “breeding-back”
projects.
The breeds
to be compared are exclusively those currently used in these projects because otherwise
I could include a pretty large range of breeds. But mind that those breeds
included in “breeding-back” are by far not necessarily more aurochs-like than certain
other primitive breeds.
I did not
even try to include Heck and Taurus cattle. The reason why is explained down
below.
The first
question is the level on which the breeds should be compared. Basically there are four
such levels: morphology/visible traits, behaviour, genetic level, ecologic
level. The social and ecological behaviour of all cattle seems to be very similar. As to their behaviour to humans, although breeds are
known to differ more or less in temperament, it is a fact that the behaviour of
cattle is very plastic and depends a lot on on environment and socialization. How easy cattle are to handle is actually a trivial anthropocentric question that is barely of biological relevance, and there are no
aurochs to compare with anyway.
How to define
and measure “ecologically aurochs-like”, including traits such as hardiness,
heat/cold tolerance and food needs? There are no living aurochs that can be
used as a model, and there are regional differences in ecological
requirements as well. The same as with genetics: there is simply not enough
data (yet) to include genetics. It seems that the appearance and morphology of
cattle is the only really quantifiable aspect for such a list. Furthermore, it
is questionable if such a split would be useful at all, because most, if not
all, of the optically aurochs-like breeds are very hardy and robust and would
be on the other list as well.
So I
decided to focus on external appearance and morphological traits only, as the only quantifiable aspect that is also comparable with tangible evidence from wild aurochs. But this is not
easy either. At first I had to figure out how to set up the character criteria.
This is arbitrary already because I had to decide what is “a trait” at all.
For example, you could say “wild type colour” is one trait, or you could
include all the (partly speculative) individual loci that have to be right for
a correct aurochs colour to evolve. It becomes more difficult when it comes to
quantitative traits, because these are often highly polygenetic features. That’s
the next problem: this schematized list assumes that all the characters are equal.
But they obviously are not, because some traits are way more polygenic than
others. Furthermore, traits may be connected to each other due to pleiotropy
and developmental cascades. The question is if we can ascertain where this is
the case (which I think is difficult) and if we should count them as one. Another
question is which traits are regulated by “original aurochs alleles”, such as
colour traits, and which mimic original traits as an artefact of selection;
f.e. if cattle are large because they were selected for increased size, is this
truly aurochs-like as well? Is this relevant at all? We surely can hardly
answer this question in a useful way. I don’t know how to usefully consider the
influence of the environment because it is rarely apparent if a difference
between two breeds is influenced by environment or not.
Another
problem is that many traits are more or less continuous, but to score the
breeds I need to categorize them somehow. This forces me to make yet more
subjective decisions: how precise should I do this? I decided to make a scale
from 1 to 3, with 1 being equal or nearly equal to the wild-type trait and 3
being not or hardly similar at all, and 2 is the intermediate trait. So the
cattle with the lowest number is the most aurochs like, and that with the
highest number the least aurochs like of those chosen for this comparison. At
first I started with 1-5, but the more precise the more complicated and
subjective it becomes. So 1-3 is probably easier and more effective.
It gets
even more problematic and subjective when considering that the breeds are not
uniform and stable. Most breeds differ from herd to herd regarding their resemblance
to the aurochs. Should we look at the most aurochs-like only, or simply exclude
the ugliest, or try to find an average? The aurochs-likeness is not distributed
among closed lines that can be differentiated, but usually distributed among the whole breed (also more concentrated in some herds than others) what makes it, again, more or
less imprecise and arbitrary. I chose to I tried to find a kind of average but
not to include those very ugly individuals that obviously were crossed with very
domesticated breeds or strongly selected. If a certain trait in a breed always has a
mediocre resemblance to the aurochs, it gets a 2. If such a trait resembles the
aurochs authentically in some individuals of the breed but in others not at
all, it gets a 2. If some have mediocre resemblance but others a very good one
it gets 1,5 and so on. And there you have the reason why I don’t include Heck
and Taurus cattle here. It would be pointless because they are way too
heterogeneous. In both of them you find a large variety of coat colours and
horn shapes and horn sizes, proportions, size of appendages and so on. While it
is clear that un-crossed Heck cattle lack some aurochs traits in general (like
a size above 150 cm, or an elongated snout), Taurus cattle would have nearly
all the desired traits but also a lot of undesired ones, so they would get a 2
for most of the characters. A more uniform but generally mediocre breed would give
the same result, what would not appreciate the fact that Taurus cattle have a
lot of aurochs-like traits but that these are never present all at the same
time within one individual, and that Taurus cattle can differ significantly
from individual to individual. I also wondered if it would be useful to
integrate Lidia then, because they are very heterogeneous as well. But I
decided to do so because they are not as heterogeneous as Taurus and Heck
cattle.
So you see,
the scheme that I worked out is quite subjective and simplified, although I did
tried to do my best. I would say this scheme is in the end still an intuitive
approach, but a systematic one.
Perhaps it
is not possible to compare the breeds in a really objective and not too
simplified way. I am open for suggestions!
My list of
characters is:
a) Body size
b) Size
dimorphism
c)
Proportions
d) Body
conformation
e) Tall
processi spinosi at the shoulder area („hump“)
f) Skull
shape
g)
Wild-type colour *
h) Sexual
dichromatism
i) Horn size
(thickness as much as length)
j) Horn shape
k) Horn
orientation
l)
Appendages (Udder, dewlap, fleshy zebuine hump)
m) Fur not
overly long
* no dilutions, E+/E+, no white spots, no
other deviant colours
A 1 for
body size means 165+ cm at the withers for bulls, a 1,5 means 150-165 cm, a 2
means 150-140, and 3 means 140- cm. Size dimorphism is intuitive because there
is no reliable and universally valid data for the respective breeds anyway. All
breeds therefore received a 2, because none of them has a dimorphism that
equals the hypothesized ratio of the aurochs, except Watussi which received a 2
because its dimorphism seems reduced even further. Bodily proportions refer to
the ratio between leg length and trunk length. Body conformation refers to
muscling, fat, and also the bulk of the trunk. The score for the processi
spinosi is intuitive. Concerning horn size, a breed also gets a 2 if the length
is right but the horns are too thin or vice versa (f.e. most, but not all,
Highlands).
|
|
a
|
b
|
c
|
d
|
e
|
f
|
g
|
h
|
i
|
j
|
k
|
l
|
m
|
|
|
Boskarin
|
1
|
2
|
1
|
1
|
1
|
2
|
2
|
2
|
2
|
2
|
2
|
1
|
1
|
20
|
|
Chianina
|
1
|
2
|
1,5
|
1
|
2
|
2
|
2
|
?
|
3
|
2,5
|
2
|
1
|
1
|
21
|
|
Highland
|
3
|
2
|
3
|
3
|
2
|
3
|
3
|
?
|
1,5
|
1,5
|
1
|
2
|
3
|
28
|
|
Holstein
|
1,5
|
2
|
2
|
3
|
2
|
1
|
3
|
3
|
3
|
2
|
1
|
3
|
1
|
27,5
|
|
Hungarian Grey
|
2
|
2
|
1,5
|
1
|
2,5
|
3
|
2
|
2,5
|
1
|
3
|
3
|
1
|
1
|
25,5
|
|
Lidia
|
3
|
2
|
1,5
|
1
|
1
|
2
|
2
|
2
|
2
|
1,5
|
1
|
1,5
|
1
|
21,5
|
|
Limia
|
2
|
2
|
1
|
1,5
|
2
|
2
|
1
|
1
|
2
|
2
|
1
|
2
|
1
|
20,5
|
|
Maremmana
|
1,5
|
2
|
2
|
2
|
2
|
2
|
2
|
2
|
1
|
3
|
3
|
2,5
|
1
|
26
|
|
Maronesa
|
3
|
2
|
1,5
|
1,5
|
1,5
|
3
|
1
|
1
|
1,5
|
1,5
|
1,5
|
1,5
|
1
|
20
|
|
Pajuna
|
3
|
2
|
1,5
|
1
|
1,5
|
1
|
1
|
2
|
2,5
|
2,5
|
1,5
|
2,5
|
1
|
23
|
|
Podolica
|
1
|
2
|
1
|
1
|
1
|
2
|
2
|
2
|
2
|
2
|
2
|
2
|
1
|
21
|
|
Sayaguesa
|
1,5
|
2
|
1
|
1,5
|
1,5
|
1
|
1
|
2,5
|
2
|
1,5
|
1
|
1,5
|
1
|
19,5
|
|
Tudanca
|
2
|
2
|
1,5
|
1,5
|
1,5
|
2,5
|
1
|
2
|
1,5
|
2,5
|
1
|
2,5
|
1
|
21
|
|
Watussi
|
2
|
2,5
|
1
|
3
|
3
|
3
|
1
|
2,5
|
2
|
2,5
|
2
|
3
|
1
|
28,5
|
There are
Lidia herds which are almost perfectly wild-type coloured (except sexual
dichromatism). But the breed as a whole has a lot of animals with the “black”
mutation and, white spots are not uncommon, and certain other deviant colours can
be found as well, f.e. roan and brindle. Watussi cattle have a lot of colours,
but most of those in Europe have this whine red colour, which seemingly has E+
as a base. Highland and Chianina get a question mark for sexual dichromatism,
because this trait is masked beneath diluting alleles, so it cannot be ascertained
if it is present or not. Holsteiners sometimes have the E+ allele, which
reveals that the sexual dichromatism is very reduced or absent in this breed. The
sexual dimorphism is very reduced in Sayaguesa as well, but there are still
plenty of cows that have brown shadings in their coat, so they get a 2,5. The
colour in Watussi is very similar in tone in both sexes, but there are cases
where the bulls are definitely slightly darker than the cows, so they get a 2,5.
Adding all
numbers, this is the result:
Sayaguesa
Boskarin/Maronesa
Limia
Podolica/Chianina/Tudanca
Lidia
Pajuna
Hungarian
Grey
Maremmana
Holstein
Highland
Watussi
This fits
my expectations very well (perhaps this is not surprising, because I did this
comparison). As I outlined, this was just an attempt to figure out how to
better compare the level of resemblance to the aurochs between different cattle
breeds.
Such a
comparison not only tries to be informational but could also be helpful for
“breeding-back”. But beware that this rating scores all traits defined here as
equal. This is OK in such a schematised table, but should be taken with caution
for breeding. Some traits are definitely more difficult to breed for than
others. Coat colour, for example, is much easier to achieve than other features
because the colours are controlled only by few loci. Body size is very
difficult to breed for, as its response to selection is weak. So a breed with
very large body size is worth a lot. Another aspect is the frequency of such
traits. There are only a few Iberian breeds with an authentic aurochs-like horn
curvature, and even in those breeds these kind of horns are not always present
(f.e. Maronesa, Lidia, Sayaguesa). So the right horns are very desirable as
well. I don’t know about the heritability of skull shape, but there are not
many breeds with an aurochs-like elongated skull (at least not many primitive
breeds).
All in all
I think that good-looking Sayaguesa are the most useful cattle currently used
in “breeding-back”. They have the large size, elongated skull, the right
proportions, well-shaped humps and some have an authentic curvature, so you get
many traits that are difficult to acquire at once. Furthermore, they don’t have
the annoying recessive dilution factors that Steppe-type cattle, Chianina or
Heck cattle have. Their sexual dichromatism is nearly absent. I have no
definitive clue on the exact genetic background of that trait in cattle, or how
easy it is to breed for it, but most Sayaguesa crosses have the desired
dichromatism when crossed with the right cattle. Luckily, Sayaguesa is the common breed of all three current crossbreeding projects (Taurus, Tauros and Uruz), and its influence in usual Heck cattle is getting consistently larger thanks to mixing with Taurus cattle.
Surely
there is much room for subjectivity and different opinions in this scheme and
my conclusion.
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