A hog nursery/finisher operation ruled to be Manitoba’s fifth case of porcine epidemic diarrhea (PED) is now proven to have been PED-negative all along.
The province’s chief veterinary office (CVO) reported Thursday that the site has now been taken off the list of confirmed on-farm cases of PED in Manitoba.
The unnamed farm in Manitoba’s livestock-intensive southeast was announced last week as the province’s fifth PED-positive hog farm following a “positive diagnostic test” for the virus (PEDv) on Sept. 30.
A complete investigation of the farm followed, the CVO said Thursday, including “repeated tissue, fecal and environmental sampling as well as veterinary assessment for clinical signs” in the farm’s hogs, plus examination of the farm’s management and any possible biosecurity risks.
With its findings in hand, plus “repetitive negative test results,” the CVO ruled Tuesday that the farm site “was not truly infected with PED.”
All animal movements and contacts from the farm were “deemed to be of insignificant risk” for the virus, the CVO said.
The hog farm premises were found to be “negative for PEDv during the time period when the initial samples were submitted,” Manitoba Pork chairman Karl Kynoch said in a separate statement.
“It was also noted that this site had good biosecurity practices and was not directly linked to any positive farm,” Kynoch wrote, nor were any “significant clinical signs associated with PED” detected in the farm’s hogs over repeated visits.
“No test is perfect”
The source of PEDv that produced the positive test from the site is still unknown, he said.
The provincial CVO requires “confirmatory retesting” of positive results to try and avoid false positives, he noted.
However, he added, “no diagnostic test is perfect,” thus the CVO runs additional tests and site followups to confirm such results.
PED causes severe dehydration and diarrhea in pigs and is generally fatal in very young animals, while older animals usually recover. The virus is not transmitted to humans or other animals, nor is it a food safety risk.
Since the virus was confirmed in Canada in January, officials have found 63 on-farm cases of PED in southern Ontario, one each in Quebec and Prince Edward Island, and four (now) in Manitoba.
In the U.S., where the virus first appeared early last year, PED has been confirmed in hogs on over 8,500 farms across 31 states. The virus is estimated to have killed 13 per cent of the U.S. herd. — AGCanada.com Network