MERIAL Animal Health held its
first combined equine, companion
and production animal CPD event at
Whipsnade Zoo on 21st July.
First speaker was Professor Jacqui
Matthews from Moredun Research
Institute and Edinburgh University,
whose talk entitled “What’s new in
equine parasitology?” covered faecal egg
counts, increasing development of
anthelmintic resistance through selection
pressure and measures to prolong
anthelmintic efficacy.
She explained that the use of drugs
to control worm populations potentially
triggers an adaptation in response to
selection pressure, meaning that
increased use of drugs increases the
likelihood of the development of
resistance. Over time, worms that
survive drug treatment pass on their resistant genes, perpetuating
anthelmintic resistance and reducing the
efficacy of drugs.
In order to reduce selection pressure
and prolong drug efficacy, Prof.
Matthews recommended targeted
dosing based on the results of faecal
egg counts to ensure drugs are used
most effectively.
Australian resistance
Dr David Homer from Merial Australia
discussed “Sustainable parasite control:
the Australian experience”, looking at
Australia’s resistance situation, bringing
in sheep as a comparative case study.
His message was: use products that
work, manage chemical exposure by
treating only when necessary and allow
for dilution of resistant worms to occur
by considering pasture management.
Hannah Lester from Ridgeway
Equine reviewed Eqvalan Duo’s Worm
Egg Count campaign with a look at the
results so far. She concluded that a large
proportion of the horses tested during
the campaign did not require
subsequent worming, confirming that
on average 20% of horses carry 80% of
the worm burden in a population, but
that owners could not be complacent as
without testing these high egg shedders
could not be identified.
Delegates then had to choose between presentations on flea and tick
control or an update on cattle
parasitology.
