CHICAGO, Ill. (Reuters) — A research study has shown for the first time that livestock feed can carry a virus that has killed about 13 percent of the U.S. hog herd, the study’s lead author said.
The findings, published this month in the peer-reviewed BMC Veterinary Research journal, support suspicions among farmers and veterinarians battling outbreaks of porcine epidemic diarrhea virus.
The fast-moving virus has killed an estimated eight million piglets since it was first identified in the United States last year, pushing U.S. pork prices to record highs.
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Its spread has been less drastic in Canada where 62 farms have tested positive for the virus, 58 in Ontario.
In the study, researchers collected feed residue from three farms in Iowa and Minnesota that had outbreaks of PED and had received feed from the same source. They fed it to five piglets in an experiment at South Dakota State University, and all became infected with the virus. Piglets that were not fed the infected feed did not get sick.
“This study helped validate that the virus was alive in the feed,” said Scott Dee, director of research for Pipestone Veterinary Clinic in Minnesota and lead author of the study, in an interview. “That had never been done before.”
The study did not determine how the feed became infected with PED. It is possible that ingredients in the feed, such as corn or soybeans, were contaminated with the virus. The feed also could have been contaminated in other ways, such as during transportation, Dee said. It did not contain pig blood products used in feed that are suspected by some of transmitting the disease.
The results of Dee’s study are “one more piece of the puzzle that we’ve been looking for,” said Tom Burkgren, executive director of the American Association of Swine Veterinarians.
The American Feed Industry Association declined to comment.
Researchers had previously established that PED was transmitted from pig to pig by contact with manure, which contains the virus. It can also be spread from farm to farm on trucks. The virus causes diarrhea and vomiting and is nearly always lethal to baby piglets.