title: Investigation of maturation requirements for Ostertagia ostertagi and Cooperia oncophora larvae.
abstract: Infection of parasite-free six to eight week old calves with doses of 50,000 mixed Ostertagia ostertagi and Cooperia oncophora larvae varying in age from seven to 42 days did not reveal a significant larval maturation requirement.
mesh_terms: D000367:Age Factors; D000818:Animals; D002417:Cattle / Q000469:parasitology*; D007814:Larva / Q000254:growth & development; D014251:Trichostrongyloidea / Q000254:growth & development*