BLUETONGUE - WHAT DOES THE FUTURE HOLD?
Bluetongue Meeting 14th April 2008 at the Stafford County Showground
The North West Club was pleased to host a meeting at the Stafford County Showground
on the evening of the 14th April 2008.
An audience of mainly British Blue breeders were also pleased to be joined
by representatives of other major beef breeds and the Dairy industry making
a total of around 80 farmers. The speakers, Alasdair King the Veterinary Manager
and Government Liaison Officer of Intervet, Kim Marie Haywood the Director
of the NBA and Jan Roggens a Belgian farmer of the Van Terbeck herd whose cattle
had been severely affected by the Bluetongue virus, were listened to intently.
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| Jackie Smith with Jan Roggens, Kim Marie Haywood and Alasdair
KIng |
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| Kim Haywood makes a point to the audience |
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| Alasdair King answers a few questions |
The message from our speakers - a very clear:
VACCINATE! VACCINATE! VACCINATE!
Good reason one:
In order to export your animals, and ‘exporting’ means selling
them into Wales, Scotland, Northern Ireland and Southern Ireland, your cattle
will need to be vaccinated by or under the supervision of a veterinarian who
will then have to issue a certificate of vaccination.
Good reason two:
As the vaccine becomes available and the protection zone is extended animals
from anywhere designated within a protection zone will be able to move without
restriction and you could well fined that a similarly unvaccinated animal but
carrying the virus moves onto a holding next to yours with devastating results.
It is worth remembering that many of us have said that it would be better if
we were all in the same designated zone, but with numerous cattle pre-movement
tested during the vector free period only a few new cases were uncovered and
those were within the current protection zone. Therefore it would appear that
the surveillance zone and those outside either of the two zones are relatively
safe at the moment and until the midges become active again. A greater risk
of contracting the disease may be incurred if cattle were allowed to move freely
before vaccination was allowed to become effective.
Good reason three:
Animals subjected to the virus have proved to have major fertility problems
with great difficulty being experienced getting them into calf and once in
calf coming back into bulling after 3 months or so and sometimes after 6 months
(foetal absorption). Bulls have also experienced infertility and even after
treatment have taken some time to come back into a good fertile state.
It was pointed out that it is illegal to vaccinate animals outside the Protection
Zone and if anyone did obtain a vaccine privately and used it on their animals
outside the protection zone they would be liable to a £5,000 fine.
Please read on for a more detailed report on the meeting.
Kim Haywood started the proceedings by way of explanation of some of the legislation
and decision making of the various government bodies of the EU, Defra and the
Scottish and Welsh parliaments and the views within Northern Ireland.
As we are aware Defra have ordered 20million doses of vaccine, which it is
hoped, will start to be delivered during May. The vaccine will be issued and
used in a controlled manner with the first issue going to the protection zone
and then extending outwards as availability of vaccine allows. It was a stark
reminder that anyone obtaining vaccine privately and using it outside the protection
zone is liable to a fine of £5,000. A question was asked as to why it
had been decided to vaccinate from within the protection zone outwards and
not in a reverse manner from outside the protection zone inwards thereby targeting
those animals at least risk and then proceeding to those at most risk. It was
explained that as soon as vaccine is used in an area that area then becomes
part of the protection zone and consequently anyone from any country can then
legally move their animals to this area if they are from the same designated
zone. This would mean that those animals which had not been vaccinated would
be at a much higher risk of contracting the virus and it was thought that this
would spread the disease rather than, as is being tried, contain it in the
most seriously affected areas at the present time.
Wales has ordered 2.5m doses from Intervet but as yet has not announced its
vaccination policy. Scotland has issued a tender for a vaccine order of 12million
doses and is considering a winter compulsory vaccine programme with farmer
administration but it was thought that on reflection this may prove too costly
and compulsion measures take too long to establish in light of the ever present
threat of spread of the disease. Northern Ireland is aiming to keep the virus
at bay by banning movements into the country but the farmers are demanding
a vaccine be ordered.
It was pointed out that there are several strains of virus and it is very important
that when purchasing or exporting animals to establish which type of virus
the country we are trading with have. The vaccine we have for the time being
is only effective against type 8 which is the type affecting us at the moment
but other countries do have other strains and it would be very unwise to import
any cattle at all at this time but even more so if they are coming from an
area infected with a different type of virus to the one circulating here.
France is endeavouring to obtain a vaccine (not the same one as we are expecting
in the UK) to enable them to protect the trade of 40,000 bulls to the Italian
market. The vaccine is considered suitable for the young bulls but is not for
release to the breeding stock.
In the Netherlands from August to December 2006 there were 456 reported cases
and from July to December 2007 6475 cases (with 4,601 cases being reported
by September). This affected 37,319 holdings and 3,670,106 cattle. The Netherlands
have ordered 1.6million doses of vaccine for use on cattle and this will be
targeted at the areas where it is known that there have been relatively low
outbreaks.
The most sobering message from Kim Haywood was left until the end when she
advised that a farmer in the UK had 50% of his herd infected in 2007 and in
2008 all of the calves were born dead.
Alasdair King gave a presentation related to the virus itself and started off
reminding us that it can spread at the rate of 5 – 10 km a day. Cattle
are considered to be ‘virus factories’ due to their size and body
mass and can often show no signs of being unwell at all. He explained that
the disease attacked the blood vessels and demonstrated itself with the animal
perhaps having a short-lived fever, off it’s food, swollen head and oral/nasal
lesions.
He advised that there are 1,000 species of midge but only 6 types are at the
moment proved to carry the virus. The lifespan of these midges can be anything
between 10 days and 3 months and the air temperature affects their response
to the virus.
No one can be sure just how the virus reached us but it is thought that a major
hatching of midges on the northern coast of France were picked up by a change
in wind conditions which carried them over the Channel and when the wind dropped
the midges were deposited on Norfolk and Suffolk.
In the UK there have been 2 – 3 deaths per farm, which has been infected,
but it has been found that the second year of an outbreak with the same virus
appears to be more severe and the same farms often become re-infected.
Whilst we are awaiting release of the vaccine in your area one of the only
means of protection for the cattle (or sheep) is a pour on to hopefully kill
the midges before they have the opportunity to bite. Intervet trialled their
product Butox®SWISH in the Summer of 2007 by clipping the hairs from the
top and bottom of the legs after the animal had been treated and exposing freshly
caught midges to them. This did in fact paralyse the midges immediately before
they had the opportunity to bite and the midge died shortly afterwards. This
trial was undertaken again 14 days and 28 days after application and had the
same effect.
The BVT8 vaccine itself is administered by a 1ml injection under the skin and
a further 1ml injection for cattle after 3 weeks it then takes a further 3
weeks after the second injection to reach full immunity. The following year
the vaccination will need to be repeated around two weeks prior to the risk
of midges becoming active again. The vaccine has not shown to be any different
to the vaccines already in use and should itself be treated in the same manner.
A question was asked if it was necessary to clean the needle after each animal
had been vaccinated and it was stated that as it is almost certain that a midge
vector was needed to transmit the disease and therefore no additional measures
should be needed other than the already best practises that existing vaccines
benefited from. However, as with these vaccines, once opened the BTV8 vaccine
should be used within 8 hours and keeping it longer only adds to the risk of
contamination of the vaccine itself. This was borne in mind when it was decided
to supply the vaccine in 20 ml and 50ml plastic bottles (so hopefully they
shouldn’t break if dropped!) in the first instance with other sizes becoming
available at a later date.
Overall the vaccine trial conclusions were that the vaccine was well tolerated
even by young calves and lambs and also when administered at more than the
recommended dose it did not appear to have any detrimental effects: it was
effective in prevention and reduction of the infection.
The first supplies of the vaccine will be available in early summer and will
be rolled out under controlled measures as quickly as possible.
Intervet has just launched a dedicated web site www.bluetongue-info.co.uk that
is regularly updated and is intended to keep us up-to-date with the latest
information.
Jan Roggens of the Van Terbeck herd in Belgium gave a stark presentation on
the devastating effect the virus had had on his herd. The first symptoms were
when the cows and heifers started to abort their calves, some after a few months
some after 6 months, and on testing were found to have contracted the virus.
After antibiotic treatment the animals recovered and although it was a struggle
they did manage to get some in calf again. The ones that did not abort this
time did go on to calve but some had calves that had deformities, some with
only three legs. Those calves born correct were then found not to grow and
remained very small and not suitable for breeding from. The bulls that had
the virus became infertile and even after treatment took a long time to regain
fertility and even then did not easily manage to get the cows back into calf.
This has completely wrecked their breeding regime. Some females that are thought
to be in calf and in good order are in fact coming back into bulling after
3months and some after 6 months. They, at the moment, have to decide whether
or not to try and put the females, who are displaying very irregular bulling
patterns, back into calf or wait until after a vaccination programme has been
put into place. Whichever way they decide they still cannot be certain that
the heifers will be able to produce good quality calves or whether they would
be best to let the present stock of heifers go and start again.
Jan could not express his concern for the future other than to ask us to VACCINATE,
VACCINATE, VACCINATE hopefully so that we can avoid the same fate.
A very sobering thought for us all.
Jackie Smith
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