The trace-out is completed among cattle associated with a British Columbia herd that had animals confirmed with bovine tuberculosis in November 2018.
The Canadian Food Inspection Agency reported completion of that task in late May. Trace-out activities involve the tracking and testing of any animals that came from the source herd or were otherwise associated with it in the last five years.
The CFIA said one herd in Saskatchewan of about 1,500 animals remains under restricted movement as part of the ongoing investigation. That means animals in that herd cannot be moved without CFIA permission. Fifteen herds in B.C. and 22 in Alberta have been released from movement control. Some 25 premises and 18,000 animals have been part of the investigation.
However, the CFIA warned that additional animals could be placed under movement control as testing continues.
All animals in the B.C. herd with the original case have been killed, and testing ultimately found four with bovine TB.
The CFIA said all four had the same strain of the illness, and it was different from any other cases previously found in Canadian livestock or wildlife.
“This strain is not related to past cases of bovine TB in Alberta or British Columbia or anywhere else in Canada. The United States Department of Agriculture has confirmed that this strain has not been previously identified by its laboratory service,” the CFIA said in a recent update.
The agency will start trace-in activities related to the B.C. case this fall. That involves identifying animals that entered the B.C. herd in efforts to identify and eliminate the source and prevent any other spread.