Rumen microbiome profiles of dairy cattle are affected by the presence of, and vaccination against, the abomasal parasitic nematode Ostertagia ostertagi.

ABSTRACT: Ostertagia ostertagi is a highly prevalent nematode that affects grazing cattle and impacts performance and welfare by reducing appetite and hindering weight gain. Despite its economic significance, the influence of the abomasal parasite O. ostertagi on the rumen microbiome remains unexplored. We examined the effects of subclinical O. ostertagi infection and vaccination on the rumen microbiome at taxonomic and functional levels. In an experimental trial, calves treated with vaccine or adjuvant-only were orally challenged with O. ostertagi larvae daily for 25 days; 4 groups of animals (UNF: unvaccinated, unchallenged; VAC: vaccinated, challenged; CHE: unvaccinated, challenged, high cumulative faecal egg counts (cFEC), and CLE: unvaccinated, challenged, low cFEC) were selected for whole shot

SUBMITTER: Lima J 

PROVIDER: S-EPMC12783138 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature