Manure application and PEDv
By Marg Land
Porcine epidemic disease virus (PEDv) kills piglets two to three weeks of age or younger. Photo courtesy of Linda Geist, University of Missouri
Jerry Foster, an environmental health and safety manager for Cargill Pork, based out of Missouri, is sick of talking about PEDv.
“Six months into this thing, I was already really sick of talking about PEDv,” he explained during an information session held in early July during the North American Manure Expo. “The psychological toll on all those involved is huge.”
He described a swine farm in Texas that became infected with the disease, despite being isolated – there wasn’t another pig for more than 100 miles around. The new operation was one week away from its first scheduled farrowing.
“In one day, they went from being really excited … to ‘We’re really down because when all those gilts farrow, we’re going to euthanize every pig in here.’ It’s really disheartening, really discouraging to people.”
Foster was one of three people who spoke in Springfield, Missouri, about the devastating swine virus and its effect on manure hauling and application during the special panel session.
“There’s a lot we haven’t learned,” he said. “There’s a lot we’ve got left to learn about it. It doesn’t respect distance or isolation. It’s really hard to pattern this stuff. Where we’ve had it show up has been rather surprising.”
Once again describing the swine operation in Texas, Foster said it’s not known how the disease spread to the farm. He did add that geese on the farm were sampled and tested.
“They did isolate PEDv on the feathers of those birds. Was it waterfowl that put it in there? Don’t know. Can’t say that it was; can’t say that it wasn’t. But they were able to isolate it there.”
But once an operation has the disease, it’s very hard to get rid of it.
“It’s much easier to catch it than it is to get rid of it,” said Foster. “You don’t have to try to catch it. You can do that pretty much automatically. Getting rid of it, that takes an awful lot of work.”
Research has shown PEDv does not like dry, hot conditions – three to four days in a dry environment and the virus dies. But it will survive at least 28 days in wet conditions, including sub-zero temperatures.
“You can thaw out a block of ice and still isolate out PEDv from the material you’re testing,” said Foster. “This is a nasty little varmint to deal with. Manure tends to be wet. That’s why biosecurity is such an important issue for custom applicators. This is one we don’t want to be taking to our customers because of all of the ramifications of the disease.”
It would take just a sample of pure virus the size of a pencil eraser to infect every pig in the United States.
“It doesn’t take much. A fly could carry that much. Fleas on a rat can carry that much; carry it to a farm. When they get it, everybody gets it.”
In light of this, Andrew Henson of Arm’d Custom Pumping, based in Sac City, Iowa, was also on hand to discuss some of the biosecurity and sanitation protocols he has put in place when dealing with swine manure.
“A typical meeting before we go to a new site consists of going over lines of separation, equipment placement and biosecurity,” he explained. “Before we go to a farrowing unit, I collect current data sheets from the barns and find out what they’re going through; if they’re going through (PRRS) Porcine Reproductive and Respiratory Syndrome, PEDv, etcetera.”
All of his equipment is power washed and disinfected in the field using a self-contained power-washing unit with two, 250-gallon tanks.
“Everything is power washed and disinfected. We also carry canisters and pump sprayers so we disinfect while we’re at the job, not just before and after.”
Farms are also rigorously mapped out to avoid crossing specific lines of separation, including roads frequently travelled by barn employees. All of his equipment is parked in the field to help reduce exposure to the barnyard area.
“The only thing we actually bring on site after everything is in the field is a lead pump and the pickup,” said Henson. “And then agitators are all brought on site the back way through the field so we don’t have to go through the main entrance.”
In a perfect world, he would prefer farm operators supply their own lead pump to transport the manure from the barn to the field, meaning the custom applicator can stay in the field and away from the barn.
It was a sentiment shared by Foster.
“It’s a good idea to have a farm-specific pump there that never leaves that guy’s farm and you’re not taking the responsibility for that pump or having it cleaned,” he said. “You don’t even have to go up close to the farm. If that’s something you can work out with your clients, I think that’s a really good idea to do that.”
Cargill expects custom applicators to follow a strict set of protocol when pumping and applying manure from its contracted facilities. And the key to it all? Communication, said Foster.
“Before you go to the farm, verify the status on the farm before you arrive,” he said. “Ask that producer is this place PEDv positive? Have you had PEDv? How do you know? Have you had any unusual exposures? You want to verify that before you go there. I would even recommend following up with that producer a week later. Since I was there, has anything changed in your health status? You need that information to communicate with your customers that you’re serving down the line.”
Foster stressed that equipment needs to be properly cleaned before it’s disinfected.
“Disinfectant doesn’t work if it can’t get to the surface. You want disinfectant to make it to the surface. It won’t penetrate dirt. You got to have that stuff really clean. The inside needs to be clean too. You need to be able to recirculate water through that machine, including the disinfectant, to clean the inside out.”
Cargill also requires all equipment to have 24 hours of down time before it’s brought onto one of its contracted farms.
“Disinfectants need time to work,” he explained. “A lot of people think they kill on contact and they frequently don’t. It takes a while for them to get through that cell wall and to deactivate or kill that cell. That is the reason to make sure that disinfectant has had time to be fully effective on the pathogens.
“Other farms might have different requirements. They may want you to have longer down times. They may get along with shorter down times. They may want you to use different disinfectants. They may not be worried about some of those issues. I don’t think you can talk to him too much about this.”
He urged all custom applicators handling swine manure to be very vigilant about following protocols and biosecurity rules during this fall’s manure application season.
“I don’t know of a case where any of our contract farms or any of our field people has said ‘Yes, we can conclusively trace the outbreak of PEDv on this farm back to a custom applicator,’” Foster said. “I don’t know that it’s happened. I do know the mechanics are available for it. If you take a look at how the PEDv travels, how it’s spread. It’s there. That’s why we have to know about this and take precautions, why we have to be careful.”