KANSAS CITY, Mo. – Results of a recently published study has shown for the first time that livestock feed can be a carrier of porcine epidemic diarrhea virus (PEDv). The study was published in the peer-reviewed BMC Veterinary Research journal.
Researchers, led by Scott Dee, director of research for Pipestone Veterinary Clinic in Minnesota and lead author of the study, focused on three farms as part of their experiment. One farm is in northwest Iowa, while two farms are in southwest Minnesota. Herds at the farms contracted PEDv despite implementing strict biosecurity controls. But the farms also had one factor in common — a shortage of feed that required an emergency delivery.
"The emergency delivery had been deposited into a designated external storage bin which sourced feed to a distinct subpopulation of the herd," according to the study. "Following consumption of said feed, clinical signs became apparent only in the animals that had consumed this feed, i.e. no other signs were noted in other animals consuming other feed from other bins."
Researchers collected feed residues from bins, and fed it to five piglets at South Dakota State Univ. All the piglets became infected, but piglets not fed the infected did not get PEDv.
"It was interesting to note that since neither feed source contained animal by-products, suggesting that contamination may have occurred post-processing, however, this was not proven," according to the study. "Further studies should focus on understanding the possibility of post-processing contamination as well as evaluating the ability of intervention strategies, i.e. the application of heat and pressure through the pelleting process and/or the inclusion of select feed additives which may have anti-viral effects, for reduction of this risk."
The Canadian Food Inspection Agency (CFIA) launched testing of swine feed in March to determine a possible link between feed and the spread of PEDv. But the agency reported that its research could not demonstrate that feed pellets containing blood plasma were capable of causing disease. Canada reported the country’s first positive case of PEDv on Jan. 23.
PEDv is fatal to young pigs and is only infectious to swine. The virus has killed more than 8 million piglets and spread to herds in 30 states since the disease was first confirmed in the United States in May 2013.
The journal article can be found at the BMC Veterinary Research website.