The bull appears at 0:22. Look at its horns, its morphology, its skull shape. Simply wonderful. All in all it is a very aurochs-like individual. The colour is not wildtype colour (which would be an E+//E+ genotype), but colour is an easy fix as it is controlled by only a few genes. The morphology, however, is controlled by most likely a very large number of genes and thus a bull that has the right morphology but not the right colour is much more useful for "breeding-back" than a bull with the right colour but not the right morphology. And considering that most "breeding-back" cattle so far have a morphology that is not quite there yet, this Lidia bull would help to boost their aurochs-likeness considerably.
However, this breed has to be used wisely due to its problematic behaviour. What I would do if I had the chance would be to create a herd of about 30 Chianina cows and let them be covered by this Lidia bull. The results will be F1 Lidia x Chianina that have both a full set of Lidia chromosomes and Chianina chromosomes. Then I would pick one of the F1 bulls (either the best-looking or least aggressive one), and let them cover all of the F1 cows. The resulting (roughly) 15 F2 will display a wide phenotypic variation spectrum. Some individuals might have the Lidia size and Chianina horns (not desired), or Chianina size and the horns of the Lidia P individual. It requires luck to get an individual with horns and morphology like the Lidia bull, Chianina size and Chianina leg length and an E+ phenotype without visible dilution factors et cetera. I would pick the best bull of the F2, also taking the behaviour into account for pragmatic reasons, and let him cover all of the F2 cows. Maybe the F3 individuals will be pretty good already and also more or less homozygous for the desired traits due to the consequent line breeding. If not, one could repeat the process endlessly (that way, highly inbreed and genetically homozygous laboratory mice lines have been produced that are used for genetic research. The so-called purging of deleterious alleles produces genetically homogeneous lines that do not suffer from an inbreeding depression), but I would expect that the F3 would be pretty good already. It would maybe lack horn volume for an average aurochs, but it would likely be within the variation of the European aurochs (compare with, for example, the Prejlerup bull). The genetic diversity would be narrow, but my goal would not be a large, genetically diverse population but rather a couple of high-quality, genetically comparably homogeneous individuals that are suitable for improving the aurochs-likeness of other herds. Bulls from such a line could be used as sires on other "breeding-back" herds. That way the potential of this Lidia bull would be used for the breeding of aurochs-like cattle.
Unfortunately this is all a phantasy scenario of mine, but it is always great to see that there are such great Lidia bulls around.
It would be very interesting to see this breeding scenario being attempted.
ReplyDeletehttps://youtu.be/i5c0K5acG8w
ReplyDeleteI also like its behavior : seem to be fearless but not "crazy for fight"; it observes, charge and stop, without wasting energy or risking getting hurt.
ReplyDeleteYou missed one point about how lab mice were produced using that inbreeding method.
ReplyDeleteThe lab mice were inbred for 20 generations to make them genetically homozygous.
9 out of 10 started in-breeding lines of thoose lab mice died out in genetic disease before 20 generations.
1 out of 10 inbreeding lines managed to survive the bottle neck.
If 9/10 breeding lines die out is no problem with lab mice, but it might be an expensive experience if you breed cattle.
I know, I didn't want to get too extensive on the lab mice. I did not suggest a completely homogeneous cattle line, especially as genetic diversity is needed in these cattle (they are not lab animals). I don't think that inbreeding is successful beyond four generations except with a lot of luck. That's why I did not want to get too much into the lab mice line breeding.
Deletehttps://en.natmus.dk/historical-knowledge/denmark/prehistoric-period-until-1050-ad/the-mesolithic-period/the-aurochs-from-vig/
ReplyDeleteIt seems to me some low percentage of this breed should be introduced into any back breeding attempt. In addition to the physical traits, having some of these aggression genes circulating in the wild population is probably correct and good for the species.
ReplyDelete