Autumn is here – which makes now a critical time for farmers to address liver fluke disease among their cattle, says Michael Chambers, Director of Invetus, Australasia’s largest veterinary contract research organisation.
Liver fluke infects cattle and sheep, but often goes undiagnosed because it shows no obvious signs or symptoms. Most of the damage is caused during the earliest stages of the parasite’s development, as it travels through the animal’s liver – and its impact can cause significant losses, with an estimated $50-$80 million per year in productivity losses alone.
As Michael explains, early May is the optimal time to treat cattle, as this is when liver fluke are most likely to be maturing to two weeks old – which is its youngest treatable stage:
“Autumn is the best time to begin treatment, as it’s when the largest amount of immature fluke are found in the animal. This immature stage of the parasite is the most destructive to cattle, as the fluke migrate through the liver, causing hemorrhaging and scarring along the way – so it’s vital to begin treatment before they can do too much damage.”
Michael also points out that tackling the problem now “will also ensure that animals don’t need to be treated so often, which is often the case with products that only target the adult stage of fluke.”
There’s another reason why treatment at this time is so helpful, as Michael continues: “Treatment now will also ensure that animals are not carrying a fluke burden over winter, when pastures can be of low quality and quantity.”
Farmers can take various steps to help control liver fluke at this time – one of which being the importance of good grazing management. “Keeping animals out of swampy areas with fencing helps to break the liver fluke lifecycle. This, combined with using drenches at strategic times of the year, such as autumn – as well as knowing via monitoring what fluke drenches work on each property – are all crucial for effective fluke control.”
While triclabendazole was introduced as the main drench treatment 30 years ago, triclabendazole-resistance can be a challenge for farmers wanting to protect their herd. Invetus has lately been involved with the identification of triclabendazole-resistance on cattle properties, as well as the implementation of new control programs – and Michael says that this has “allowed farmers to obtain much better fluke control, reducing the negative impacts on the cattle and bringing down the overall prevalence of liver fluke on a property.”
Triclabendazole-resistance has also led animal health company Virbac Australia to create two products, which are effective even against triclabendazole-resistant strains. Most importantly, they’re able to target immature fluke as young as 2 weeks old, as well as early immature and adult liver fluke. Nitromec is the world’s first triple combination injection for cattle, and Virbac’s latest fluke treatment NitroFluke contains a unique combination of nitroxynil and clorsulon, to provide a best-practice 3-stage control including the dangerous 2 week old fluke.
NitroFluke can also be used alongside other worm treatments, such as Cydectin Inject or Cydectin Long Acting – and Virbac are the only company with products registered against 2-week-old fluke, making their products an indispensable part of any successful control program.
As Michael states, liver fluke’s impact on the growth rates and fertility makes them “one of the most pathogenic internal parasites of cattle in the temperate regions of Australia. Considering the current high price of cattle, any reduction of these factors has a direct financial impact on the farmer,” he adds.
“Early fluke control helps improve weight gain, ensuring that steers reach their target weight more quickly, while also supporting the health of heifers and cows, both at joining and calving. All these efforts improve the overall health of the animals, which ultimately brings more money to the farmer. Taking action now really is a win-win, both for the animals and the overall success of a farm.”