The challenges that liver fluke present to dairy farmers are increasing. With milder winters making longer grazing seasons possible, liver fluke related disease is becoming more of an all year round threat.

It’s now more important than ever that dairy farmers understand the flow of events that begin with the fluke egg and finally lead to a traumatised liver. Such a liver can reduce herd yield and, as a result, lower the financial potential of the farm.

Understanding the challenge

Liver fluke disease can cause losses in a range of different ways, including: death; clinical disease; poor growth rates; reduced production; and liver condemnations.

Aside from the clinical manifestations, liver fluke is also associated with increased susceptibility to other diseases such as clostridial and metabolic diseases.

It is important that farmers understand the challenges that liver fluke present, both in terms of management and treatment. Once these are understood, you can build targeted control measures that are also cost effective.

A ‘dry’ farm is not an assurance against liver fluke infection and, consequently, a liver fluke control programme should be implemented on all dairy farms irrespective of whether they are wet or dry.


The importance of a control programme

A liver fluke control programme may vary from a simple dung sample – to rule out the presence of the parasite. Other measures could include: grazing management; diagnostics; and pharmaceutical treatment at drying off.

The absence of a liver fluke control programme on any farm – wet or dry – can lead to the disease associated with the parasite and production losses.

On farms where liver fluke disease has been confirmed, it’s vital to implement a planned treatment regime, which is likely to deliver meaningful health improvements for the herd.

Fluke dosing and the dry period

In recent years, regulatory bodies contraindicated the availability of flukicides with a wide range of activity in terms of the age of liver fluke. This was due to a lack of residue data to support their use in dairy cows during the dry period.

This contraindication presented dairy farmers with a dilemma in terms of maintaining cow health and managing the transition of the cow to ensure she calved down in optimum condition.

Recognising the management challenges presented by the regulatory guidelines, Elanco Animal Health embarked on a project to generate data to support a claim that would make triclabendazole available to dairy farmers for use during the dry period.

Following a submission of data to HPRA (Health Products Regulatory Authority), Elanco Animal Health was granted a licence for Fasinex 240 to be used in dairy cows during the dry period. The data showed that the residues in milk decrease slowly during the dry period and then, decrease rapidly after the onset of lactation.

In fact, a pre-calving interval of 35 days after dosing was found to result in residues decreasing to the level of the MRL, or below that level, within 48 hours of calving.

Consequently, milk for human consumption can be taken from 48 hours after calving. If calving occurs before 35 days after treatment, milk can be taken after 35 days plus 48 hours after treatment.

Fasinex 240, which contains triclabendazole, has been welcomed by the dairy market. Its activity against adult, immature and early immature fluke gives dairy farmers important additional options in controlling liver fluke on their farms. Click here for more information