The Huron County Health Unit says a calf from a farm in the Blyth area has tested positive for rabies.
It says the calf from a farm about 95 kilometres north of London was sent for testing on Feb. 27.
The health unit says the Ministry of Agriculture, Food and Rural Affairs is working with the farmer and a veterinarian to implement a precautionary confinement period for the other cattle that were in the group with the infected animal.
Health unit spokesman Patrick Landry says there were "hundreds" of cattle on the farm and they'll be quarantined for "well over 30 days."
Landry says the calf and a skunk that was sent for testing in December both tested positive for the arctic fox strain of rabies, which has been found in cattle in neighbouring Perth County.
He says it isn't known how the calf contracted rabies.
