7 June 2002

Wet weather flystrike threat

FREQUENT showers and warm weather brings the threat of flystrike on some lowland farms.

But lack of a cold spell in early spring means few flocks have succumbed to nematodirus this year.

Keeping on top of stock inspections will allow producers to spot flystrike problems early, says Mike Sharp senior vet investigation officer at Luddington Vet Lab Agency. "Warm days with intermittent showers increase flystrike risk. Risk is also higher for scouring lambs."

But many flocks have escaped nematodirus this year, usually a problem in May and June, says Mr Sharp. "Nematodirus requires a cold spell followed by daily temperatures above 10C to develop. In a normal year large numbers of larvae will hit pastures in May/June. But this year we had a mild early spring, so by the time lambs were grazing the risk period had passed."

But producers should plan ahead to control gut worms as the risk period approaches, warns Mr Sharp. "Control strategies will vary widely between farms, depending on grazing system. Ewes and lambs should be drenched and held for 24 hours before they go on to silage aftermaths to keep these clean."

With increasing numbers of producers turning to faecal egg counting as an indicator of when to dose, he urges caution. "While it is a useful tool, sometimes egg counts can appear low when lambs are scouring heavily due to a dilution effect. Seek vet advice; dont automatically assume there is no need to dose when egg counts are low." &#42