“Not a lot of producers are routinely testing, because it can be a time burden,” says Wade. “I still encourage producers to do it, because once we do, we have a really good snapshot of what is happening on the operation, which allows us to create the most strategic deworming plan.”

When producers send fecal samples for diagnostic testing, he reminds them to specify their desire for liver fluke analysis. A general diagnostic test will only look for common gastrointestinal parasites.

Liver flukes are worth consideration

While liver flukes rarely result in cattle death losses, understanding their underlying effects is important for cattle health and an operation’s bottom line.

“The biggest problem with flukes is their impact on production.” — Jody Wade

“The biggest problem with flukes is their impact on production,” says Wade. Liver flukes are one of the more complex parasites in beef production. Before setting up camp in the bile ducts of the liver, juvenile flukes cause damage in the small intestine and abdominal cavity as they travel, leaving cattle with weakened immune systems and lost growth potential.

Cattle with liver fluke infestations may go months without showing clinical signs. Depending on the level of infestation, cattle can experience loss of appetite, rough hair coat, decreased performance, weight loss and poor reproductive efficiency.¹

“The ones that really pay for it on the back end are the packers,” Wade continues. “When they start harvesting cattle and find flukes, they have to condemn those livers.” Liver condemnations can lead to significant financial losses, particularly for feedlots and processors.

Liver flukes require special management

The survey highlighted common deworming practices among respondents, with pour-on and injectable dewormers being the most popular application methods. However, one-third of respondents said they were unsure if their dewormers include fluke coverage.

“Right now, there are only two products in the marketplace available for effective fluke management,” says Wade. “When selecting a product for liver fluke control, it’s important to look for a product that has clorsulon or is specifically labeled for fluke coverage.”

He further explains that the available products are only effective against adult stages and do not kill juvenile flukes, which cause the most damage. But, when applied correctly, the elimination of adult flukes can disrupt the production cycle and reduce the risk of pasture reinfestation.

Understanding the life cycle of liver flukes, from egg to adult, is essential for implementing effective control measures. Unlike other internal parasites, flukes need an intermediate host to propagate. For flukes, this is a common freshwater snail. As shown in Fig. 3, the fluke larvae migrate to snails, where they multiply. Once they exit the snail, cattle can ingest them by grazing on infested grass or drinking infested water.

While it isn’t realistic to keep cattle away from areas that also attract freshwater snails, sustainable deworming practices like pasture rotation and refugia (the practice of only deworming high-risk animals), are also ways to help control liver flukes and other parasite populations.