Speculation that Porcine Epidemic Diarrhea virus hitchhiked from China to the United States got a boost from research by Dr. Scott Dee of Pipestone Veterinary Services at Ottumwa, Iowa.
Dee found that conventional soybean meal, organic soybean meal, lysine, Vitamin D, and choline chloride all created a PED-friendly environment, while in the other ingredients the virus died. Dee’s work was published Saturday in BMC Veterinary Research.
“In the presence of certain feed ingredients, under conditions that simulate a trans-Pacific journey,” Dee said, “contaminated feed ingredients, if they're the right ones, could have certainly supported virus survival throughout this entire 37 day trip.
Brian McCluskey, executive director for science, technology and analysis services for the U.S. Department of Agriculture, said Dee’s work supports the government’s findings on possible ways the virus could have entered the country, but that it has not yet convinced the agency of PED’s root cause.
About seven million piglets have died in the United States since the virus arrived. The epidemic has waned this winter and may now be under reasonable control.
It entered Ontario via plasma from dead pigs that was supposed to be safe to use as a feed ingredient. It is still showing up in some herds this winter, but Ontario has a strategy to eliminate the disease and it appears to be working.
There have been 93 outbreaks in the province, far more than any other part of Canada.
“It is evident from [Dee’s] research and some of ours that the PED virus can survive in feedstuffs and the containers that deliver the feedstuffs for the time it takes to transit from Asia to the U.S.,” McCluskey said in a statement.
“This is still not conclusive evidence that PED virus arrived in the U.S. by one of these pathways.”
Dee’s study also tested two treatments and found that each of them could kill the PED virus if applied to a contaminated ingredient.
Dee said he hopes his findings will lead to more research on animal diseases that have not yet made the leap here from other continents, such as foot and mouth disease and African swine fever.