|
21st July 2008
Important
Notice to Perth October sale vendors In Blue Tongue
Protection Zone
17th July 2008
As of 21 July 2008 at 00.01hrs the Protection Zone
will be extended to cover Worcestershire and the districts
in North Yorkshire (Scarborough, Ryedale, Hambleton & Harrogate),
Cheshire (Macclesfield, Congleton & Crewe and Nantwich)
and Greater Manchester (Rochdale, Oldham, Tameside
and Stockport) previously in the Surveillance Zone.
The change follows delivery of additional doses of
Bluetongue vaccine.
Please see the following link for
more information
http://www.defra.gov.uk/animalh/diseases/notifiable/bluetongue/latest/index.htm.
BLUETONGUE
Guidance on the disease vector and potential
mitigation measures
The following guidance provides information on the
vectors that spread Bluetongue and the mitigation measures
that may be appropriate for some situations. Farmers
and veterinarians may wish to consider the following
advice.
The
Culicoides Midge
The Bluetongue virus is spread by
Culicoides species of midge.
There are 47 different species of
Culicoides but only a few species are
able to carry the virus. Some of these species
are present throughout the UK. The risk of
virus transmission is related to the
number of midges present.
Culicoides behaviour
-
Populations fluctuate,
and peak in May/June and September/October.
-
Daily
activity peaks at dusk/dawn.
-
Some of the most
widespread UK species breed around animal dung.
Culicoides mitigation measures
-
No insecticides
are authorised specifically to act against Culicoides
-
Deltamethrin-based
compounds have performed best in tests, however,
they only offer limited coverage of animals and provide
1-2 days protection at best.
-
Generic repellents are
only effective for a few hours at best.
-
Because they
do not entirely remove the risk of an animal contracting
bluetongue and their short period of protection,
in addition to economic and environmental considerations,
the Scottish Government does not advise insecticide use against Culicoides on
farms as a practical and cost-effective control measure against Bluetongue.
-
Although
the Scottish Government does not advise the use of
insecticides as a control measure, it supports it
application for short-term protection of animals
transiting through BTV restricted zones. Animals
and their vehicle must be sprayed prior to travel.
-
However,
in the event of an outbreak insecticide treatments
may be required for certain specific livestock movements.
-
Any
insecticides should be used in accordance with the
manufacturers instructions.
Culicoides breeding sites can be potentially
reduced by:
-
Moving dung heaps away from livestock (>50m
where possible), or covering heaps with a plastic,
watertight cover.
-
Scrape the perimeters of heaps/slurry
pits regularly to a depth of 6-10cms (where the majority
of larvae reside).
-
Housing of animals
in an enclosed space (where the means are available
to close doors, and cover entrances with mesh) during
peak periods of Culicoides activity may
reduce biting rates to a greater or lesser extent,
-
No
one measure will prevent midges biting animals. However,
the use of a combination of the measures listed above
will sequentially reduce the risk of midge bites
and hence reduce the risk animals becoming infected
with BTV.
|