Beef cattle in Louisiana are continuously exposed to infections with parasitic gastrointestinal nematodes (commonly known as roundworms). The life cycle of these parasites is direct; they do not need an intermediate host. Adult worms in cattle shed eggs that are passed in their feces. These eggs hatch and develop into infective larvae that climb on growing forage and are ingested as the forage is consumed. These larvae develop into adults and the cycle is completed within 14 to 60 days.