Fluke is an internal parasite affecting a wide range of species. Cattle and sheep can be affected. The parasite has an unusual life cycle and produces a wide range of symptoms. Increasingly we are experiencing more problems in Leicestershire due to climate change and movement of livestock.
What are the symptoms?
Dairy cattle– lower milk production, increased milk fever, poorer body condition than expected and changes in milk quality. In clinical cases of fluke the cow may scour and the symptoms can resemble Johnes disease. The degree of impact will depend on the proportion of animals affected in the herd
Sheep- in addition to the similar symptoms to cattle of poor thrift there is an acute infection that can occur prior to the shedding of fluke eggs which can result in sudden death. More chronic forms present with scour and “bottle jaw” ( fluid swelling and oedema under the jaw )
What is the life cycle? How is it spread?
Infection is typically introduced onto farms from infected animals entering the herd or flock. Sheep and cattle from infected areas from the West of the UK may bring in carrier animals that look normal and then they deposit fluke eggs in the dung on the pasture. If the temperature is above 6 degrees C the eggs develop and then contaminate the pasture. A snail then consumes the developing fluke and a life cycle through the snail results in contamination of the pasture again with microscopic fluke stages which survive on the pasture.
These are consumed again by cattle and sheep and the process multiplies. Warm wet winters and summers allow for extended survival of all stages of the fluke life cycle. Cold winters kill off the snails and fluke life stages and slow down the life cycle. The time taken for the full life cycle from egg to fully adult laying fluke is 5 months. Once the fluke life-stages are eaten by the cow or sheep it takes 10-12 weeks for the fluke to develop into an egg laying adult fluke.
Why is fluke more of a problem now?
Climate change has favoured the fluke and we now can experience fluke multiplication in the winter and the summer. If we experience cold winters this reduces the burden of infection on the pasture. With warm winters and extended autumn grazing the risks increase significantly.
How can we test for fluke?
In dairy herds bulk milk can be tested and is a simple and cheap way of monitoring for fluke. Poor producing animals can be blood tested for Fluke antibodies. Later on in the disease process faeces samples can be checked for eggs. It must be remembered though that fluke only produce eggs after 10-12 weeks after ingestion and this will not work for diagnosis of acute fluke in sheep as mortality can occur prior to egg production. Slaughter house information can be very useful in terms of monitoring the farm. Fluke forecasts can also be used to help predict fluke.
What treatments can I use?
There are limited treatment options for dairy herds. A holistic approach is required to establish the source of infection, time the treatments to help block spread and progression and to work through the best options for the herd. Typically you need to use two to three products depending on the stage of lactation and handling facilities
How can we help?
A common mistake is to find a fluke product off the shelf and simply use this at random times! This is not a fluke control plan. The risk with this approach is that you may end up with fluke resistance or inadequate control. Many of the treatments only treat certain stages of the fluke and timing is crucial.
You have to Measure, Manage and Monitor the disease and create a low risk fluke situation on your farm.
We can help sort out a surveillance, treatment and management plan for you. Give us a ring today!