Download Elimination of Markings - Huzulen im Club Hucul Austria

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Elimination of Markings = Loss of Precious Attributes
(Résumé of the Discussion about Piebald Huzuls)
To preserve the precious pool of genes of the huzul breed,
to avoid extinction of particular genes
and consequently of specific attributes
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selection is to limit to the most necessary
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phenomenological diversity is to preserve by genetic diversity
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precedence is to give to as much stallions of a fair quality as possible
and not to a few only, even though excellent.
Explanation
For a certain attribute, i.e. piebald colour yes or no, a certain gene-locus is relevant, occupied by two
genes (alleles), one from the mother and one from the father. One of these genes puts through, that
is determines the appearance, dominates.
We recapitulate the problem of piebald huzuls. Piebald huzuls bear the Tobiano-gene which is responsible for the piebaldness of a huzul horse exclusively. The Tobiano-gene is dominant, that is who
bears it is piebald and has at least four white legs, keeps however a non-piebald head. As nearly all
piebald huzuls stem from Zefir and most of Jasmin one has avoided through decades to mate piebalds with piebalds but mated piebalds with plain coloured huzuls. According to this breeding rule
the relevant gene-locus has one Tobiano-gene and one plain gene if the horse is piebald, and has two
plain genes if it is not. Mating piebald huzuls with plain coloured huzuls then leads to 50% piebald
huzuls and 50% plain coloured huzuls. The plain coloured huzuls don’t bear a Tobiano-gene, that is
they cannot pass on a piebald colour even if one of the parents was piebald.
In case you mate piebald huzuls among each other, descendants may have two Tobiano-genes, and
those produce piebald huzuls exclusively even if mated with plain coloured huzuls.
Markings are not controlled by the Tobiano-gene but by different ones. Markings can show up at legs
and head. According to Stachurska (Anna Stachurska, Odmiany a srokatość, KONpolski 3/2012, S.22)
three gene-loci are responsible independently for markings. A marking to be visible requires primarily
a marking-gene at one of the marking-loci, secondarily however additional gene constellations. One
of these marking-loci is in neighbourhood of the gene-locus for piebaldness. If the Tobiano-gene
causes piebald colour there, it stimulates an eventually existing marking-gene to show up (Stachurska). This can lead then to additional head markings at piebald huzuls. Plain coloured descendants of
piebald parents don’t bear the Tobiano-gene, therefore it cannot stimulate an eventually existing
marking-gene. It follows, that plain coloured huzuls with piebald parents don’t have markings more
often than plain coloured huzuls without piebald parents.
It’s apparent that the population of plain coloured descendents with piebald parents cannot produce
piebald colour anymore. That is the Tobiano-gene is gone though at least one parent had it. So with
adequate selective mating strategies one could wipe out the Tobiano-gene at huzuls, piebald huzuls
would disappear. This looks trivial. But contrary to piebald colour there are attributes with our huzul
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horses where you don’t know whether they are present or absent. Then randomness of mating and
unthought and biased selection can induce the loss of genes which stay for very specific and typical
attributes - the loss of certain genes may first be in parts of the population, on a long term globally as
well. This danger is the greater the smaller the breeding basis, the more selection, the more mating
restrictions. Thereby even “coupled” genes may vanish.
The huzul horse is well known and preserved in genetic programs because he holds particular attributes (genes) which are single in the world of horses. Unnecessary selection because of outwardnesses (unimportant particulabonnyr features which suit or do not suit) endangers the gene-pool.
Markings are outwardnesses and besides can be bonny (/pretty). Straight legs, a head like a pony, a
perfect body, this all may please judges and/or breeders, but these features not only are untypical
but also reduce the gene-pool drastically if selection takes place this way - consciously or unconsciously - and thus endanger particular attributes of the huzul horse.
The unintentional extinction of precious genes happens especially when only a few stallions, so called
champions, are active and have a high mating rate - that’s to say reproduction takes place on a limited basis of genes. Well known this also accelerates the increment of the inbred factor. When
breeding for “preservation” it is much more important to have as much stallions of fair quality as
possible (that is a diversity of genes) than to use stallions of excellence of which there are only a
few (with a limited number of genes).
An excellent stallion, bred to perfection, cannot materialize any further improvement. The important
attributes (gene-loci) are charged genetically identical (homozygous), the relevant genes are dominant in most cases and so even the population of mares cannot enter something attractive new. It
only can get worse again. Stallions which aren’t as perfect may however allow for different combinations of genes and so other attributes of advantage may show up.
I appeal to the breeding commission respective the judges and registrars to revaluate the huzuls of
recent years which had fair quality, especially typical huzuls with small markings only, and to license them (if not too late). As long as stallions were in national care it may have been reasonable to
limit their number for economy reasons; where the breeder/owner himself asks for license there is
no reason to limit the number of (fair) stallions. However, in case you want to limit the population of
huzuls for the reason that the special attributes of the huzul horse are out of use nowadays (to preserve them has ideational character mainly and needs state-controled care) it is even more important to pay attention to the preservation of typical attributes by maintaining diversity and retarding
developments which prefer biased, unbalanced likings.
The diversity necessary to preserve the gene-pool of the huzul breed gets cut back (gets reduced) not
only by excessive demands on high ratings and/or biased selection of the breeding commission but
also by the practice of usability testing and championships. Diversity with respect to the gene-pool
requires diversity with respect to the phenotypes for breeding; diversity with respect to the phenotypes for breeding is promoted by a diversity with respect to breeders. The frequent and obligatory
participation on usability testing in order to qualify for the annual championship privileges a few huzul holders which are well off (privileges them together with their eventual biased preferences regarding horses) and forces offside experienced breeders because of costs (training, transport, absence of farm, staff). Adapted regulations and financial incentives could emphasize the instinct of
experienced breeders and assure diversity in breeding for the benefit of the gene-pool of the huzul
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horse. It’s the nature (environment/human-animal symbiosis in daily usage) which knows what is
good for breeding if you let it do. And that’s the way piebald huzuls survived last century though the
military interests nearly had eliminated/erased them (there is only one piebald huzul mare now
mother of all piebald huzuls: Pisanka, 1940, grandmother of Zefir)! And it may well be that together
with the Tobiano-gene a piece of amiability and companionability was saved - just because in the
daily use both correlated positively (human-animal symbiosis, a kind of fitness to survive).
Christine & Peter Jansen
Club Hucul Austria
www.AlpinPonyAustria.at
30.3.2012