Page 20 - Silverstream 2021 Catalogue eBook

BREEDING ‘POLLED WITH PUNCH’

Over the last few years we have been striving to breed more polled cattle. Our issue in the past with this has been that we believed the polled
cattle didn’t have the strength, performance or the constitution of their horned counterparts. We could have brought in a homozygous polled
bull years ago and easily polled our entire herd very quickly but the problem with this is we didn’t believe there was such a bull that we could
have used without compromising the strength and quality of our herd that we had carefully selected over many years. We always thought it
was important to keep our quality herd we had established and still keep infusing quality genetics from France, Australia and North America
that suited the type of cattle we were trying to breed that also suited our environment here in this country.

We were very fortunate that we had used polled genetics many years ago over our really traditional French type of cows so we had started to
get polled progeny that we really liked and fitted into our herd well. Bulls like Silverstream Benchmark and Silverstream Bookmaker were two
of the first polled animals that had an impact in our herd, and in this catalogue you will find daughters of these bulls that are still in our herd.
2009 was probably a significant year as it was the year Silverstream Evolution and Silverstream Enticer (Bookmaker son) were born. These
two bulls have had more impact on our herd than any other bulls and they were both polled. Enticer went on to sire Silverstream Geddes and
Evolution has been the single most influential bull we have ever used. Silverstream Manhattan our new homozygous polled sire we believe
will be the next most influential bull to Evolution and you will note he is out of an Evolution cow and sired by Silverstream Geddes. A few
years after them came Jensen who was a complete outcross of polled genetics as he was out of a polled cow but sired by Tinor, a horned full
French sire. He has also played his part with many lovely daughters and is also the sire of our new up and coming homozygous polled sire
Silverstream National.

These original home bred polled sires that we have used have only had a sniff of polled genetics in them but by taking our polled breeding
program slowly we have been able to breed polled cattle that we believe are just as good and in many cases better than their horned
counterparts. As you run your eyes over the bulls out in the paddock we believe you cannot see a difference in type, strength or constitution
of the polled and horned bulls. Three years ago 50% of our calves being born were polled. Last year over 70% were polled. This spring we
predict that over 90% of the calves born will be polled. In our herd the type and quality we are breeding has always been paramount and I
would like to note we have never used a polled bull for the sake of him being polled. We have only selected sires that we believed had the
attributes that we have always strived for and if they were polled it was a bonus. Nowadays we have such a huge selection of polled bulls we
can find a polled herd sire that meets our needs.

While we have been firm on breeding more polled cattle due to the animal welfare issues associated with dehorning we certainly would not
discourage anyone from buying a horned bull. You would be far better off using a top end horned bull than a middle of the road polled
sire. If managed right you can also use a horned bull and still get all polled calves anyway. For those unsure about how the poll and horned
genetics work it is explained below.

POLLED AND HORNED EXPLAINED

In most cattle the horn/poll gene action is simple with the poll allele (P) being dominant to the horned allele which is recessive (H). Every
parent has a pair of alleles for the each gene and they pass on one of these alleles for each gene to their calf. So the calf gets one allele from
the bull and one allele from the cow to make its pair. What this means in the poll/horn scenario is that if a calf gets a two polled alleles it is
considered homozygous polled; if it gets one polled and one horned allele it will be physically polled, but it will be referred to as heterozygous
polled or a carrier; if it gets two horned alleles it will be homozygous horned and will be horned. See Diagram 1.

Genotype Phenotype
PP Homozygous Polled
PH Heterozygous Polled
(Scurs Possible*)
HH Horned

Diagram 1
Since the polled allele is dominant to horned, if you mate a homozygous polled bull to a group of females then all of the offspring will be
polled. This is shown in Diagram 2 where a homozygous polled bull is mated to a herd of horned cows. This is the same scenario if you
mate a Horned Hereford bull to an Angus cow (as all pure Angus are homozygous polled). In this case 100% of the calves are heterozygous
polled, in other words they all have a polled appearance or phenotype, but carry one horned allele. In Diagram 3 a heterozygous polled bull
(PH) is mated to heterozygous polled cows (PH). In this mating it is expected on average that 25% of the calves will be homozygous polled,
50% will be heterozygous polled, and 25% will homozygous horned. This means about 75% of the calves will be phenotypically polled and
25% horned, even though the bulls and cows were all polled. Diagram 4 shows that when a homozgous polled bull is mated to heterozygous
polled cows the progeny will all have the polled phenotype (physically be polled) but on average 50% of them will be homozygous polled
while the other 50% will be a carrier of the horned gene. In diagram 5 when a heterozygous polled bull is mated to homozygous horned
cows, on average 50% of the progeny will be expected to be horned and 50% to be polled but these polled calves will still be a carrier of
the horned gene. Diagram 6 shows a homozygous polled bull mated to homozyogous polled cows. In this situation all progeny are polled in
appearance and can only be homozyogous polled as they only carry polled alleles. In Diagram 7 when a homozygous horned bull is mated to
homozygous horned cows all progeny can only be horned as they are carriers of only horned alleles. Note that these matings will have the
exact same results if the genders are mated the opposite way round, e.g. A homozygous horned bull mated over homozygous polled cows will
still have progeny with the same genotypes as Diagram 2 shows.