Metastrongylus apri the pig lungworm

Abstract

Observations out of doors demonstrated that the viability of embryonated eggs in soil was adversely affected by dryness. This was confirmed in laboratory experiments.The resistance of embryonated eggs to temperatures below freezing-point was observed both out of doors and in the laboratory.The rate of development of larvae in the intermediate host was reduced as the temperature fell.The longevity of the infective larvae appeared to be largely determined by the longevity of the earthworm intermediate host, although they were able to survive for a time when separated from the earthworm's tissues.The longevity of eggs and larvae under natural conditions and the persistence of infection on a pasture are discussed.