A second treatment for nematodirus may be required in some cases. The highest risk is where there was a percentage of young lambs in the flock at the time of treatment.

n many cases these lambs may have picked up a parasite burden since treatment, with white drenches recommended for treatment possessing no residual activity. Lambs aged six to 12 weeks are most prone to infection as grass consumption increases.

As such, lambs under nutritional pressure and forced to graze more or at a younger age will face the greatest challenge.

Affected lambs will develop a scour and if allowed to progress this can quickly progress to diarrhoea.

Lambs will quickly become dehydrated and mortality can be high in untreated cases.

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Early nematodirus infections forecast

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