Correlation does not mean causation, but it can be a good place to start investigating a link. And, sometimes, that apparent link turns out to be valid. Earlier this week, the CFIA confirmed that PEDv DNA detected in hog feed (which contained hog plasma) was capable of causing infection.
CFIA’s statement, released earlier this week says:
Testing has determined that PED virus was present in samples of US-origin plasma obtained at the third-party manufacturer for Grand Valley Fortifiers. This plasma was used as an ingredient in feed pellets produced by the company. Testing with a swine bioassay has determined that the plasma ingredient contains PED virus capable of causing disease in pigs.
Further testing will be done to assess if the feed pellets are capable of causing disease in piglets, and results are expected within days. Testing will continue to confirm a direct link between the feed and the spread of the disease, as the virus is only confirmed in a single ingredient at this time.
The CFIA is working closely with the company to confirm the effectiveness of the recall, and is closely examining company records to see where potentially affected product was distributed.
The CFIA is also reviewing records of other imports of swine plasma and will work with the Council of Chief Veterinary Officers and the pork industry in Canada to proactively manage the possible risk of transmission through feed.
As the investigation continues, additional actions such as recalls may be necessary to minimize the potential that feed could contribute to the transmission of this disease in Canada.
PED virus DNA has been found in feed common to several of the now 21 farms with confirmed infection. At least one feed manufacturer in Ontario voluntarily recalled its piglet feed products after the finding. The last confirmed infection was yesterday (you can click here for a full run down of counties affected). Manitoba and PEI also confirmed the first cases in those provinces. Hog plasma is used as a feed ingredient in Manitoba; one feed mill is currently testing its sources as a precaution.
Earlier last week, I called the Animal Nutrition Association of Canada hoping that hog feed wasn’t to blame, or, even better that hog plasma was not being used in hog feed on a regular basis. While I recognize that hogs are omnivorous and including animal protein or products in feed makes sense, my question, flat out, was “Did we learn nothing from BSE?” (BSE, for those who need the reminder was spread through feeding byproducts of sick cows back to healthy cows. Cows are herbivores, I should add).
The representative from ANAC said that, as of last week, the science supported the inclusion of hog plasma in hog feed. We know now, that that is no longer the case. The answer to my BSE questions was more guarded, but the reason given for the practice was that hog plasma was the superior product, boosting efficiency and saving on costs.
I love science, don’t get me wrong. If a practice is proven safe, then, even if it’s cringeworthy (I get that hogs have no issue eating hogs, it’s the biosecurity factor that trips me up), then it’s safe. CFIA had, just last week, failed to confirm that VIABLE virus has been found in feed, only that DNA of the virus has been found. The optics, however, don’t look good. And, furthermore, in my mind if we’re using animal byproducts in feed to be fed to omnivores let’s have a species barrier as risk management, no? Please?
And a final update: the vaccine. It should be noted that the PEDv vaccine is not a miracle drug — it will not cure the disease, nor will it eradicate it. The vaccine, at best, will prevent death from the virus in some animals and curb some of the production efficiencies moving forward. For example, a sow that is infected may lose the entire first litter of piglets. Subsequent litters may be fewer in number; the vaccine may prevent this long-term loss of productivity per sow but it won’t prevent an infection or cure the disease. The vaccine is not for a sick animal, it is for the rest of your herd once you’ve found it. Strict biosecurity protocols are the best defense — the vaccine is another tool but not a cure nor even a means of 100% avoidance.
For more details on biosecurity measures, signs, symptoms and more on the PEDv outbreak, click here.