OAHN Bovine Project: Parasitism in Grazing Cattle in Ontario
Project Lead: Dr. Jessica Gordon (University of Guelph)
To view the full report, please download the PDF here: https://www.oahn.ca/wp-content/uploads/2021/03/PROJECT-SUMMARY-OAHN-Bovine-Project-Parasitism-in-Grazing-Cattle-030493.pdf
In 2019, OAHN supported fecal sample submissions for fecal egg counts (FEC) of the gastrointestinal nematode (GIN) species. The eggs from GIN are indistinguishable under a microscope, so FEC reports a grouped GIN species count. The relative pathogenesis of GIN species varies by type. The most common GIN in cattle in Canada are Ostertagia ostertagi, Cooperia oncophora and punctata, and Nematodirus helvetianus. GIN are spread between cattle on pasture, when eggs laid by mature worms in the gastrointestinal tract of infected cattle are excreted in the feces. These eggs hatch in the environment and mature to L3 larvae, which are infective if ingested. Pasture is required for transmission, so cattle housed entirely indoors will not become parasitized.