Industry warns sheep farmers to prepare for action against liver fluke

Sheep farmers must be on their guard against liver fluke this autumn
Sheep farmers must be on their guard against liver fluke this autumn

Sheep farmers must be on their guard against liver fluke this autumn, says Philip Skuce, a leading scientist at Moredun and part of the SCOPS Steering Group.

He says: “We are now approaching peak liver fluke season and, having experienced one of the mildest winters on record across the UK, followed by a very wet summer, some areas of the country are going to have a very high level of liver fluke this year.

This is because this type of weather provides ideal conditions for the mud snails that are an essential host during part of the fluke’s lifecycle.”

However, it isn’t going to be the same for everyone, Dr Skuce warns: “Some parts of the UK have been very wet, particularly in the west, whereas others such as the south east have been relatively dry.

As a result, NADIS has specifically forecast that liver fluke risk will be high in Scotland, North West England and North Wales.”

Sheep are at risk of picking up liver fluke infection from now through the winter. Clinical signs of fluke infection include:

-Abdominal pain, with animals reluctant or unable to move.

-Anaemia, seen as pale eyes, gums etc.

-Submandibular oedema or ‘bottlejaw’.

-General ill-thrift.

'Unexpected deaths should be investigated'

Advice from SCOPS is that unexpected deaths should be investigated and that farmers should investigate fallen stock and request abattoir feedback on evidence of fluke or any fluke damage.

Dr Skuce says: “This feedback is invaluable. It was overlooked as a source of information in the fluke storm that hit the UK in 2012/13 and could have prompted earlier treatments had farmers had that information.”

Routine diagnostic testing can also help build up a picture of what’s happening on farm. There are a number of diagnostic options available, typically based on testing blood or faecal samples.

Avoidance strategies can help too. For example, fencing off particularly wet areas on farms, even temporarily, will help reduce exposure.

If possible, sheep should also be moved off high risk fields onto safer grazing at this time of year. Lower risk fields would include those with no or few mud snail habitats, fields not grazed by sheep or cattle earlier in the year, or fields growing stubble or forage crops.

Dr Skuce continues: “Unfortunately, we know many sheep farmers will simply treat their animals for fluke without any evidence of infection or of how effective any treatment has been."

"There are a number of flukicidal drugs available, each with its own spectrum of activity against different stages, and I urge farmers to use the SCOPS website to get to grips with this."

"Reports of resistance to triclabendazole (TCBZ), the drug of choice for treating acute fluke in sheep, have been increasing."