Encyclopedia of Parasitology

2016 Edition
| Editors: Heinz Mehlhorn


Reference work entry
DOI: https://doi.org/10.1007/978-3-662-43978-4_2259

Named in honour of the German scientist Ostertag.


Genus of the nematode family  Trichostrongylidae.

General Information

The adult worms (female about 10 mm long) live in the rennet-bag (4th stomach) of cattle. The larvae 1–3 develop within 3 weeks outside of the body. When larvae 3 are taken up with grass, they enter the glands of the rennet-bag and grow there via 2 molts until maturity. Males and females live free in the small intestine. The prepatent period takes 18–23 days in Ostertagia ostertagia and O.circumcincta.

Life Cycle

Copyright information

© Springer-Verlag Berlin Heidelberg 2016