IN the UK, an increased incidence
of rumen fluke eggs in dung
samples, and in the number of
cases of acute larval
paramphistomosis, has recently
been reported.
This increase has been reported
predominantly in cattle but also in
sheep. It is also currently diagnosed in
approximately 30% of sheep and 40%
of cattle in Northern
Ireland.
Clinical
signs include anorexia,
dehydration,
ill thrift,
rapid weight
loss, listlessness, anaemia and severe
watery scour, which may contain
blood following a period of
prolonged straining.
A large fattening unit near
Banbury in Oxfordshire which fattens
approximately 3,000-4,000 animals
per year, purchasing 10-24 month old
store cattle, mostly from the West
Country and Wales to graze and
fatten, recently reported a problem
with their cattle.
In January 2013 the farmer noticed certain groups of housed
cattle were not doing as well as they
should be, with reduced feed
conversion rates, much reduced
weight gains, extended periods to
slaughter, and in general not looking
as good as he would expect.
The farmer weighs cattle regularly
to ensure effective weight gain, and
these animals were not hitting weight gain targets.
Not all groups or all animals within a group were affected and it
was difficult to decide on the exact
origin of the affected cattle as they
were mixed on the farm, but
essentially they were from Wales,
Welsh borders and South West
(Somerset, Dorset mainly).
All cattle are routinely given a
combined closantel and ivermectin
injection (Closamectin Injection for
Cattle, Norbrook) on arrival at the
unit and vaccinated for IBR. This is
repeated at housing.
I visited the farm on 21st January
to inspect and sample the affected
groups. Laboratory results showed a
very low worm burden in faecal
samples. Pooled faecal samples
returned positive for liver fluke eggs,
and on serology 4/12 were positive
for liver fluke.
Pooled faecal samples and
serology results did not point to liver fluke as the problem so further
investigation was warranted, and it
was decided to follow some animals
to a local abattoir to inspect the
rumen and reticulum for rumen fluke.
The farmer had heard other
fatteners were having similar
problems and, when investigated
rumen fluke emerged as a cause.
Although most animals were
slaughtered at a large abattoir,
approximately two animals per week
were slaughtered in a local and easily
accessible abattoir.
Inspection of the reticulum and
rumen of these slaughtered animals
showed extensive infestation with
rumen fluke. Additionally, the abattoir
routinely washes the tripe for sale,
and therefore inspections of the tripe
reported a similar scene as being a
regular finding for the previous 6-8
weeks.
There is no licensed treatment for
rumen fluke but oxyclozanide is
recognised as the only flukicide
effective against both the adult and
immature stages of rumen fluke, and
I recommended Levafas Diamond
(Norbrook), under veterinary prescription, for the treatment of the
affected animals.
On 20th February the farmer
purchased the product and treated the
affected groups. Subsequently, post-
treatment faecal samples returned
negative for both liver fluke and
rumen fluke eggs, indicating
successful treatment.
No further rumen fluke
infestations have since been found at
the abattoir.
Following treatment the affected
groups grew on well and further tests
during the year proved negative for
both liver fluke and rumen fluke.
The conclusion was that the wet
summer of 2012 was a big
contributing factor to the problem.
The farmer had spoken to other
cattle dealers during the winter of
2012/13 who had experienced similar
problems, initially reported as poor
response to flukicide treatments, but
using flukicides which were not
effective against rumen fluke.
As in this case, when investigated
it was rumen fluke that was found to
be the cause of ill thrift, and all
animals treated responded very well.