The significane of Nematodirus helvetianus eggs which have survived on a pasture throughout the winter in the transmission of infection to calves.

A field experiment was carried out to determine the significance of Nematodirus helvetianus eggs which had survived throughout the winter in the transmission of infection to calves turned on to a pasture in the early summer. The calves became infected but did not exhibit symptoms of clinical disease. It was concluded that eggs which survive the winter are unlikely to be associated with outbreaks of disease.