The spring-rise phenomenon: Seasonal changes in the worm burdens of breeding ewes and in the availability of pasture infection

Abstract

Extract

The “spring-rise” or post-parturient rise in the faecal egg count of breeding ewes in New Zealand was discussed by Brunsdon (1964) who later demonstrated the importance of the phenomenon as a source of trichostrongyle infection for lambs (Brunsdon, 1966a).