Wet weather brings increased parasite risk

Livestock producers are being urged to keep an eye on the weather, because wet conditions are ideal for fluke to thrive and pose real challenges to cattle and sheep this year, even in areas where there has been little risk before.

"We are approaching the main season for fluke and with the changes in weather patterns and two previous wet seasons, there is a serious risk of an increase in the fluke challenge this year," warns Novartis Animal Health veterinary adviser Saul Harvey. The wet spell will also increase worm challenge on pasture as increased moisture allows worm larvae to migrate away from dung pats to be ingested by stock.

Pointing out that the high risk period when the infected cysts were particularly active in the pastures was from late August through to winter, Mr Harvey said there were already definite signs of snail activity in regions much further east than before. "The recent rains and warm temperatures at up to 2o centigrade above normal in some parts of the UK will kick off the fluke cycles this year"

he said.

In cattle liver fluke is a serious disease that can lead to severe financial losses, with falls in milk yield of 500g / day over a 305-day lactation, as well as reduced weight gains of up to 1.2 kg a week in growing cattle. A flukicide that kills all three stages of fluke including immatures should be used in this high risk period, such as Fasinex 240 which is a low volume concentrated formulation and can be given through the floating hook doser for ease of administration.

Liver fluke also affects the condition and growth of sheep and often leads to "sudden death" in acute cases. The first indication of fluke in sheep may come after slaughter at the abattoir, where damaged livers are often condemned due to liver fluke damage. To avoid these problems a flukicide such as Novartis’s Fasinex, that kills all three stages of fluke - early immature, immature and adult - should be used, said Mr Harvey. Fasimec Duo S, with ivermectin, should be used if worm control is also required.


Mr Harvey advised cattle farmers to dose their cows with a flukicide two weeks after they had been housed to clear out all the fluke ingested by the livestock while they were out grazing infected pastures.

"It is particularly important that they use a product like triclabendazole (in Fasinex 240) that will kill all stages of fluke after housing, because using an adult-only treatment will leave immature fluke around to continue to cause liver damage and that will affect productivity over the winter period," explained Mr Harvey.

He pointed out that once ingested, early fluke stages burrowed down through the liver causing substantial production losses. Adult fluke then caused further damage as they finished their development in the livers’ bile ducts, feeding on the animals’ blood and protein before being passed out in the faeces to restart the cycle.

"It is important that cattle and sheep farmers across the UK are aware of the fluke risk this year and ensure their animals are protected against the consequences of this damaging disease, because it could occur anywhere across the UK," he added.