title: Negative interactions between Ostertagia ostertagi and Cooperia oncophora in calves.
abstract: The interactions between Ostertagia ostertagi and Cooperia oncophora were studied in calves by concurrent and sequential infections. A reciprocal negative interaction between the 2 species was found in sequential, but not in concurrent infections. This result was supported by the finding of serological cross-reactions. It is suggested that the negative interaction is immunologically mediated. The depression of weight gain found after infection was similar for O. ostertagi- and C. oncophora-infected calves.
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology* / Q000469:parasitology; D003429:Cross Reactions; D005260:Female; D008297:Male; D010029:Ostertagiasis / Q000150:complications / Q000276:immunology / Q000469:parasitology / Q000662:veterinary*; D014251:Trichostrongyloidea / Q000276:immunology*; D014252:Trichostrongyloidiasis / Q000150:complications / Q000276:immunology / Q000469:parasitology / Q000662:veterinary*