Dairy herds struggling with liver flukeshould consider a pre-turnout, flukicide-only lactating cow treatment to clearout adult flukes.
If fluke has been diagnosed, theres astrong case for treating housed milking cows in February and March. At thistime of year the animals have been housed for three to four months and thereshould only be adult fluke present in the cattle and treatment now withoxyclozonide will kill adult flukes in the bile ducts and prevent them layingeggs that will contaminate pasture. Treatment before cattle go out to grasswill also help take the pressure off the other available flukicide treatmentslater in the year, says MSD Animal Health veterinary adviser Matt HaslamMRCVS.
Fluke problems are escalating, whilst at thesame time the available flukicide control options are being restricted.Consequently, he says it is crucial that dairy farmers work with their vet toobtain a diagnosis of their liver fluke situation and threat on their own farm.And then discuss the latest best practice flukicide usage advice.
From a diagnostic point of view, a bulkmilk test is the first starting point. The result will tell you if your herdhas been exposed to liver fluke. If the result is negative you still need toremain vigilant particularly if your farm is wet but if it is positive yourvet will need to carry out further investigation. This may involve takingfaecal samples for analysis or even blood sampling any thin or scouringanimals.
Matt Haslam says it vitally important thateveryone works together to follow good codes of practice for the control ofliver fluke. We can no longer afford to blanket treat large groups of animals.And flukicide usage guidelines and milk withdrawal periods must be followedaccurately. For example, oxyclozanide available as Zanil in the UK has a72-hour milk withhold.
It is also important to consider that someflukicide products, such as albendazole, have activity againstgastro-intestinal worms. Whilst this may sound like a good idea, wormerproducts should only be used when worms are a problem. If you are using aproduct with activity against fluke and worms, you may be inadvertentlyselecting for resistance in the worm population, which could cause significantproblems in the future, he says.