Tracker shows high gutworm exposure this grazing season

A new parasite tracker for England, Scotland and Wales is showing an increased gutworm risk but generally low liver fluke exposure this grazing season.

The tracker from Boehringer Ingelheim Animal Health UK, which collects ELISA bulk milk test data from 90 British dairy farms, highlights increased cattle exposure to the gutworm Ostertagia ostertagi in cattle.

However, liver fluke exposure, relevant to cattle and sheep, is low in most places apart from an area in south-west Scotland.

Gutworm risk

August 2020 data showed that about 80% of tested herds now have high levels of Ostertagia ostertagi antibody in a bulk milk sample,

“Dairy herds that have not treated for worms during the grazing season should consider testing a bulk milk sample.

See also: Everything you need to know about liver fluke in cattle

“In addition, producers should be mindful that the warm and wet autumn weather will promote ongoing larval activity on the pasture and could leave youngstock at ongoing risk of parasitic gastroenteritis,” warns Boehringer’s ruminant technical manager, Sioned Timothy.


The tracker shows that 68% of farms tested presented no or very low levels of fluke antibody in the bulk milk samples.

Those that tested positive were predominantly in westerly areas.

“This is most notable in south-west Scotland. Livestock in this area are potentially being exposed to infective fluke on the pasture and, as a result, there may be a risk of acute fluke disease in sheep,” says Ms Timothy.

“While acute fluke disease is less common in cattle, beef and dairy producers should still be alert to the potential for lost productivity in infected cattle, as infections become established.”

Farmers can view the tracker or sign up to receive on the Beat the Parasites website.

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