'But if she's got 200 eggs per gram, she's contaminating the soil with her faeces, which contain the worm larvae which will then in early winter start to infect the lambs born into that pasture.' 'If a ewe's in reasonable condition she can take a worm burden than won't affect her production,' he said.

Worm burden is defined as the number of worms an individual host carries, and is generally measured by counting the parasite's eggs in a dung sample.ĭr Roberts said ewes with a worm burden of less than 100 eggs per gram were unlikely to see a reduction in their productivity, but higher counts were an issue. 'Normally we'd have a hot dry summer, and the vast majority of winter worm eggs died in the faeces so they don't contribute to the winter's worm burden,' he said. Swathes of the state's sheep farming regions were drenched in the first weeks of February, leading toīut while livestock losses were minimal, the increased germination of pasture across the state caused by the rain has led the Department of Agriculture and Food (DAFWA) to issue a warning for a less visible threat â€” increased parasite activity among livestock.ĭAFWA veterinary officer Danny Roberts said it was unusual for such a warning to be issued at this time of year. Sheep producers across WA have been urged to monitor signs of increased worm burden in their flocks, following unseasonal downpours across large parts of the state earlier this month.

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