With spring around the corner, Will Barker, from Castle Vets, takes a look at the threat posed by liver fluke and keeps one eye on lambing preparation. He spoke to reporter Alex Metcalfe.
THE days are getting longer but Barnard Castle vet Will Barker is keen for farmers to make use of the continued chill to combat liver fluke.
The parasite can cause untold harm to sheep and cows if left untreated and the Castle Vets leader has made vigilance his watchword this month.
“Liver fluke is a parasite of sheep and cattle which has quite a complicated life cycle – part of which is in the mud snail,” says Mr Barker.
“The larvae emerge from the mud snail and develop on the pasture – on a dewy morning they crawl up blades of grass where they can be eaten by a sheep or cow.”
The fluke larvae then develop further within the animal and migrate to the liver.
Mr Barker adds: “You end up with the adult liver fluke in the liver of the sheep or cow – this then lays its eggs which travel back to the gut and are excreted in faeces.
“They then hatch on the grass, infect a mud snail and the cycle begins again.”
Mr Barker is keen that farmers make the most of the winter to take the fight to liver fluke.
He adds: “At this time of year we know that the mud snails will not be active due to the cold and many cattle have now been housed for several months.
“At this stage, therefore, we feel it is a good time of year to carry out fecal samples for liver fluke eggs as we know that enough time has passed that liver fluke present in sheep or cows are in the adult stage and are therefore producing eggs.”
Liver fluke can be both insidious and devastating to a host.
It comes in two main types – acute and chronic.
Mr Barker adds: “We see acute fluke where a large number of larvae are ingested very quickly and hatch at the same time causing massive liver damage and potentially death. But the more common presentation of the disease is animals doing poorly when they only ingest a few larvae off the pasture causing low level liver damage – this is chronic fluke.”
Production loss tends to be the main presenting sign for this type of fluke ingestion.
The disease tends to be more common the further west you go and the wetter the climate gets.
But Teesdale is still in its firing line.
“We do see it in Teesdale and the distribution from year to year varies dramatically,” adds Mr Barker. “So it’s really important to see if it’s present in a herd of a flock and whether there is actually any need to treat.”
Several chemicals are available to treat liver fluke either through injections, oral drenches or “pour-ons”.
However, Mr Barker says it’s important the treatment matches the life cycle of the parasite.
He adds: “The different chemicals available kill different stages of the life cycle so it’s important to consult a vet over whether you need to treat at all.
“It’s also an important part of quarantine procedures for any stock introduced to a herd or flock where it may have previously been present.”
Meanwhile, lambing is on the horizon in the dale and Mr Barker wants farmers to keep the so-called “three Qs” at the forefront of their minds.
He adds: “There’s a lot that needs to be done to prepare for successful lambing – first of all you must ensure that the ewes are eating the correct amount of a high quality diet so they produce healthy lambs that are not too big or small and that they also produce a good quality and quantity of colostrum.”
Key to this is silage and hay analysis, says Mr Barker and having ewes scanned to see how many lambs they’re carrying is also a helpful move to judge the feed required at a critical time.
Mr Barker adds: “If there are any concerns about a ewe’s diet it’s also possible to blood sample between six and ten ewes pre-lambing – to check their dietary energy and protein requirements are being met.
“This is especially important in the early lambing period to make sure they’re as healthy as possible.”
The early lambing period can also be a tricky timeframe to negotiate – with livestock vulnerable to a number of other ailments.
Mr Barker adds: “If they are born healthy it’s important they stay that way and avoid post-natal diseases like watery mouth disease, joint ill and spinal abscesses.
“These are all bacterial diseases that are acquired in a dirty lambing environment – especially through the navel.
“The key to avoiding these diseases revolves around ensuring really good hygiene in lambing pens and that the lambs get the three Qs of colostrum management – a good quantity of quality colostrum after birth, as well as promptly dipping navels after birth in strong iodine or a product such as super 7.”
