Target your flukicides
Liver fluke has been a major pest on both cattle and sheep farms over the past few years. The wet years of 2008 and 2009 caused such an increase in mud snail numbers that even on 'non-fluke' farms the parasite started to cause problems.
From a sheep farmer's point of view, there are two types of liver fluke infections.
The first, and most dangerous, is acute fluke, which is caused by hundreds of immature fluke munching their way through the liver and causing massive damage in the process. Often lambs with this condition will just die suddenly even though they may be in good body condition.
The problem with acute fluke is that there are relatively few products that kill immature fluke. Therefore, where acute fluke has been diagnosed, it is essential that a product that is effective against immature fluke is used.
The other type of fluke infection is chronic fluke, often seen in older sheep and essentially caused by mature fluke that sit in the bile ducts and drink the animal's blood.
Poor body condition, a bottle appearance under the jaw and loose wool are symptoms frequently seen with this condition. When treating sheep with this condition there is much more scope in terms of product choice.
As sheep farmers, we need to get away from trade names and start looking at the active ingredients that are in the flukicide. In my experience, using trade names has led to many mix-ups where sheep farmers have used products that did not work on their farms but were unaware because the active ingredient was being sold under a different trade name.