According to the NADIS Parasite Forecast, sponsored by Merial Animal Health, the rain and storms following previous dry spells could increase the threat of lungworm in the coming weeks. Other highlights from the forecast, which is issued to vets and SQPs in the UK, include a lower risk of Parasitic Gastroenteritis (PGE) among sheep, lower snail infection rates for liver fluke and a continuing risk of blowfly strike.


The period between August and October sees a heightened risk of clinical lungworm disease. The hot, dry weather during June and early July has reduced the incidence of lungworm. However, heavy downpours, such as those seen in recent days, can result in faecal pats breaking up and distributing larvae onto pasture.
The symptoms of lungworm infection include increased breathing rates, coughing, a rapid loss of condition, reduction in milk yields, and even death in severe cases. Often the only indication of infection in adult dairy herds is a marked reduction in milk yield.

Treat whole herd for lungworm

Fiona MacGillivray, Merial Animal Health's Veterinary Adviser says: "Lungworm should be treated as soon as possible after its onset in order to limit the risk of permanent lung tissue damage, and it is important to treat the whole herd. A suitable wormer can be used to control both lungworm and gutworms in youngstock.  It is important that it provides persistent protection against re-infection with lungworm, allowing cattle to continue grazing pastures without risk of further disease for that period."


On gutworm the NADIS forecasts warns of the dangers for those using a 'dose and move' strategy where youngstock are moved onto pasture which has already been used earlier in the season.
While the poor weather in autumn 2012 led to a high level of winter snail infection and consequent high risk of fluke disease in Scotland, Wales and western England, this summer's dry weather is likely to have reduced snail infection rates. However, NADIS points out that there is no room for complacency as previous levels of infection were very high.
The risk of blowfly strike will continue throughout August in lambs, but should be much less likely in adult sheep following shearing. NADIS says that the choice of dip or pour on preparations in lambs will largely depend on meat withhold times.


Details of the Parasite Forecast can be seen on the NADIS website, which now also includes the ability to watch a 'webinar' video of this month's forecast at www.nadis.org.uk.