Dr. Scott Dee vividly remembers a day in early January 2014 that found him head first in a hog feed bin, scraping material off the sides.
He was getting samples because pigs in some barns in Pipestone, Minn., thought to be “bulletproof” from disease due to strict biosecurity, had contracted porcine epidemic diarrhea virus.
The illness ravaged many American hog operations that year, killing millions of piglets. Dee did not know how it had entered Pipestone barns.
His tests revealed PED could travel in feed, the first time feed was proven to be a source of infection. Since then, his research has shown other diseases can be carried in feed and feed ingredients. Among them is African swine fever (ASF), the deadly illness that decimated China’s hog industry and has spread elsewhere in Asia and Europe.
There is a concentrated effort to keep ASF out of North America, where it could devastate a multibillion-dollar industry.
Dee, the director of applied research for Pipestone Veterinary Services, told participants of the online Banff Swine Seminar Jan. 5 that his research and that of others has changed the way countries handle feed risk.
Canada implemented the first-ever national livestock feed program in March 2019, a major protection that the United States has not been able to replicate, said Dee. The program outlines import requirements and a permit process for plant-based feed ingredients imported for livestock.
Research has also resonated in China, which is now rebuilding a herd that once comprised about 50 million sows and was reduced to about 15 million by ASF.
“The feed risk, the Chinese are very, very concerned about this,” said Dee.
“They consider feed a major risk factor. There is plenty of good information in China that shows that ASF virus entered farms through contaminated feed.”
As a result, all hog feed is pelleted and all of it is cooked for three minutes at 85 C before being fed.
“ASF is still circulating in China. There’s no interest in eliminating it so it’s not going away. It’s still there,” said Dee.
“There’s a lot of vaccines being used in China, which is a big black box. These are live vaccines. My guess is there’s not a lot of quality assurance or quality control over these products in some cases, so there could be vaccine strains circulating in the population as well.”
The effects of a reduced herd and major expansion efforts are generating big dollars in the Chinese industry, Dee added. A weaned pig sells for US$250 at a $40 cost of production. Breeding animals are at a premium.
“Gilts, anything that breeds, is going for at least $600, maybe $800 a gilt (for) any kind of quality or genetics and there’s about $100 cost of production.”
Lots of pigs, production and ASF virus remaining in China are concerns because many ingredients for North American operations are imported from China.
Dee’s research shows ASF virus remains stable for weeks in many kinds of feed ingredients used on this side of the world. Soymeal and soy-based ingredients appear to be particularly good carriers.
Putting feed in quarantine for an extended period, or heat treatment, are among the measures that reduce or eliminate risk of ASF virus survival in feed.
Minnesota swine veterinarian Gilbert Patterson studied U.S. port data and found that China, Ukraine and Russia were the main international sources of soy-based hog feed to the U.S. in 2018-19. ASF is present in all three countries.
In those two years, the U.S. imported 104,000 tonnes of soy product from those three countries, while exporting about 48 million tonnes.
“It’s silly that we even have to deal with that, but that’s the way things work today in global trade,” said Dee. “So that’s crazy when you think about it. Putting our agricultural industry at risk over 104,000 metric tonnes of soy. That’s crazy.”
Canada’s regulations require importers to acquire permits for certain ingredients. It recently implemented an additional questionnaire for the import of plant-based meal products from countries with active ASF cases.
A directive sent Jan. 5 reads, in part, “in cases where the processing of the plant-based meal has not been verified and endorsed by the competent authority of the country of origin, further processing or other mitigation measures will be required by the importer once the product arrives in Canada.
“These measures will help ensure the risk of transmission of African swine fever via contamination of these products has been mitigated.”