As we are coming into the ram
selling season, I thought it might be of interest to sheep farmers to give my
thoughts on the merits or otherwise of some of the claims that are often used
to suggest one’s rams are better than someone else’s.
I would like to make it clear that I am a passionate ram breeder and as such I am not a neutral independent commentator on the following; however I would like to think my opinion is a well informed and an objective view
Firstly, you do need to cast a
cynical eye over what is often being claimed as sometimes it’s nothing more
than marketing dribble used to sell rams and adds little (being polite here) or
no genetic value to the rams.
Myomax: This is a Texel
specific gene test only, so if someone is advertising Romneys or any non Texel
breed (e.g. suffolks) with a single and/or double copy of this gene, then they are not pure, they are crossbreds:
e.g. a Romney that has had a Texel put through them; it could be ½ Romney, ¾ Romney etc. If it has a double copy it would have to of
had a Texel put through the flock at least
twice. Good luck to anyone who wants to do this, but be
aware of what you are buying. If you buy any rams with a myomax gene, then
check that the breeder is also testing for the blind gene that is associated
with Texels to ensure you don’t bring that into your flock. One other point about myomax is that one copy
gives you roughly a 10% gain in the eye muscle area, but what needs to
remembered if you buy a ram with a lousy eye muscle, 10% more of a crap eye
muscle may not be as good as a ram with a good eye muscle and no myomax gene.
Worm Star test: This
is approximately 80% about growth
and 20% about worms. So I personally consider the name of this to
be somewhat misleading as it’s principally about growth rates, simplistically
it could be renamed the growth star test. A scientist has advised me on more
than one occasion, if a sheep does have good growth rates then logically it is
probably handling any worm burden better than those that don’t. The most reliable data you get from SIL is in
fact ebvs on growth rates (young stock at least), so this test adds little, if
not nothing, in my view.
CT Scanning: For CT
Scanning to add genetic value to the rams you buy, the breeder needs to be scanning
a sufficient sample size of each sire they use, say 20 to 25 sons (some may
argue a few less) and if they do, then they are providing you with good
information. However I am personally
unaware of anyone scanning these sorts of numbers per sire. The reason being is because of cost, but
unfortunately CT scanning only a few rams simply provides you with phenotypic
information, i.e. what the animal looks like as opposed to genotypic
information (the genetic makeup of the animal).
In other words genetically you don’t know whether the ram at issue has
the genes to provide you with more meat or not, it may do but it may not. You
need to find out how many rams per sire the breeder is scanning before
assessing whether it adds any genetic value to the rams you are considering
buying.
We only keep twin ewes and use
twin rams: Where you have a stud breeder who
records all the information they should do and are on SIL, then this is just a
crap marketing statement that adds no value to the rams you buy, in particular
in terms of fecundity. Simplistically
the easiest way to demonstrate why is:
you have two rams, one a single, the other a twin, the single is out of
ewe that has had 6 sets of twins and then this single ram, while the twin is
out of ewe that has had 6 singles in a row, then has this set of twins (note in
reality I would hope that most breeders would have culled such a ewe after two
singles in a row, if it’s not a terminal breed). Accordingly if you are looking for the ram
that is likely to provide you with most fecund progeny (i.e. more multiples),
then clearly the single ram is the one you would take hands down. SIL’s ebvs for number of lambs of born would
also back this up. Accordingly such a
policy in a stud programme is likely limiting that stud’s progress. Note hypothetically if two rams are exactly the same with one
being a twin, the other a single, then I too would take the twin every time.
All rams for sale from top 35% born, or 25% born: This always makes me laugh, without more
information how is this impressive!. In
reality on its own this simply means they have retained 25 or 35% of what was
born, for sale. If from top 25%,
then based on what: that their still
alive, which makes them better than the others or top 35% on SIL which means
that they will be selling some awful rams that have good figures. I don’t know anyone who is culling their best
ones and selling their bottom 25%.
Personally I would be more impressed with someone selling 50% of their
rams born, if when you go and look at them, they are impressive with good
consistent figures, which would suggest to me such rams are more likely to pass
on the characteristics and performance I am looking for because of the depth of
quality in the stud.
We only retain ewe hoggets that get in lamb: On the surface this sounds impressive,
but you need to ask how long is the ram put out with them. I, for instance, only put ram lambs out with
them for 17/18 days and usually get around 60% in lamb, if I put them out for
two rounds I am pretty confident a very high percentage would get in lamb. I don’t, because I don’t want to lamb for
months and I want to wean my hogget lambs the same time as the ewes. Accordingly you need to ask more questions
about this before determining whether this is something that is impressive and
is of value to you.
Sheep 50k and sheep 5K: I
don’t intend to go into the merits and economics of these genetic tests in this
article, however please note the fact someone advertises that they have or are
using such tests means nothing on its own.
If they have, then ask to see the results of these tests to see that
they are using sires or selling rams that are coming up well on the traits and
performance that you are looking to improve on in your flock. The cynic in me is of the opinion that there
are some breeders using science to market their rams as opposed to improving
their genetics.
There are a lot more things I
could talk about but this is supposed to be an article not a book.
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