PEORIA, Ill. — There may be a light for U.S. pork producers at the end of a long, costly, deadly tunnel.

“We know that if we load and close that herd and create exposure, they’ll return to productivity if we clean them up,” said Bill Hollis, swine veterinarian with Carthage Veterinary Services in Carthage.

He spoke to an audience of pork producers gathered at the 2014 Illinois Pork Expo.

The acronym on the lips — and minds — of producers attending the event was PEDV — shorter for porcine epidemic diarrhea virus, a diarrhea-inducing coronavirus that has swept through 25 states in the U.S., wiping out litters of baby pigs less than 10 days old.

“Get exposure. Clean, clean, clean. Prepare the load and close. Take care of your weaned pigs. Work together,” Hollis said.

He outlined two separate procedures, one that could save 10-day-old and older pigs and one that could help create resistance to the virus through sows.

First, Identify Virus

Identifying the virus, both visually and then through official testing, is vital, Hollis said.

“We don’t see other things cause watery pipestream diarrhea, so it should be somewhat evident to the farm staff or to you if you’re looking for this virus,” he said.

For those who do spot the telltale discharge in their barns, including the growing, finishing and show pig and exhibitor sectors, Hollis had a less-than-desirable assignment.

“Recognize the virus, look regularly for the virus. If you’re seeing watery, pipestream diarrhea, capture it in a Ziploc bag and send it off to the lab quickly because we can identify it tomorrow through a PCR test,” he said, referring to the polymerase chain reaction test. “At least we can work on minimizing exposure if we know we have it.”

While pigs under 10 days old succumb to the virus, pigs over 10 days old may be saved if producers identify the disease and act quickly, Hollis said.

“If you are farrowing baby pigs and you’ve got the ability to move the older baby pigs off the farm, you have a much higher likelihood of saving more pigs so you want to know as soon as possible,” he said.

Saving older baby pigs requires some basic knowledge of how the PED virus works.

Hollis said the virus destroys the intestinal villi, causing the villi to slough off. The pig then becomes unable to absorb nutrients through food and starves to death. Pigs under 10 days of old that are nursing don’t have the ability to develop villi fast enough.

But pigs older than 10 days can survive, Hollis said.

“If you get positive identification, you have to move the oldest pigs off the farm. The diarrhea is going to infect all the pigs on the farm, and it’s going to move rapidly through the farm. The pigs that are 10 days of age or older, we believe, can take on solid food and digest it and, we believe, won’t navel suck to kill each other, get those pigs off the farm,” he said.

Hollis said a link on Carthage Veterinary Service’s website, www.hogvet.com , provides tips and tricks for getting young pigs started on solid food.

“The most important thing is you’re trying to get solid food in their gut. Get these pigs to eat feed. Get them to work to take food routinely. They’re coming off a sow where they’re used to nursing every hour, and if they’re 10 days old, they’re still looking for mom. You’ve got to encourage them to get something in their mouth every hour — get them up, get them to take on gruel, get them to take on something other than liquid milk,” he said.

Hollis said milk replacers are not an option since the milk replacer won’t induce the production of good bacteria in the gut and keep the villi working.

“If you can get that pig to eat, to take on solid food and get solid good bacteria growing in the gut, they’ve got a better chance to live,” he said.

He also said that producers may want to keep water nipples dripping so the young pigs can take on more water. Keeping the recovering young pigs draft-free also is important.

“If you’re pulling too much air through and these pigs are cold, wet and naked, they’re going to pile already so you don’t want drafts. You want to check the wind speed, the air speed, coming out of your inlets and reduce it if possible or deflect it to the back. But don’t create a draft on these pigs because they’re going to be wet. It just takes them time to recover,” Hollis said.

After those pigs are moved, he said the next thing producers need to focus on is load, close and expose and described the block-and-tackle approach to building immunity.

“We have to build immunity at the sow farm. Block the activity of movement through the sow farm. Build immunity through exposure. Take action. Clean it up, we’ve got to clean up that site. It’s constant re-exposure that creates the ongoing diarrhea,” he said.

Hollis advised producers to work with their veterinarians to develop a program to expose sows to the virus so they can build immunity that will be passed on to future litters.

“Work with your vet. Identify the virus. Identify some method to expose the whole herd. Identify feedback exposure to those sows so their milk is protection for the pigs,” he said.

Hollis said that both avenues of attack are not without risk, risk from moving animals during that time, risk of further spreading the disease through trucks, trailers and people and risk of exposing sows to the virus.

Hollis urged producers to reference materials and checklists available on www.pork.org to review a farm’s biosecurity procedures, from hauling manure off the farm to hauling feed and even pigs onto farms.

“If you’re hiring somebody to haul manure and you haven’t had this discussion, go to the website, print off the checklist. Same thing with trucks. If you’re hiring somebody to haul pigs or you’re running trucks, go to this website and there are pages on transportation and biosecurity. It can help walk you through the checklist of what can I do to minimize exposure,” he said.

Block Virus Spread

Hollis said veterinarians and researchers are looking at all the ways PEDV moves from farm to farm, even to the snowy undersides of grain trucks.

“Sow farm barriers are all in place and the frustrating thing for us in the PED explosion has been systems that already had these in place that are still breaking,” he said. “There’s something we’re moving through these systems that we haven’t figured out yet.”

Hollis gave the example of a hopper-bottom grain truck hauling DDGS to a mill that feeds several sow farms in west-central Illinois.

“The bottom of that truck is getting covered in snow and slush and ice this time of year, and it drives right over the grain dump. They open that up, and it all falls right in there, into the auger system, and when it’s frozen, it stays frozen the whole time, all the way out to the bin where the finished product goes into the sow farm,” he said.

“What I’m telling you is the degree we’re trying to evaluate to minimize risk. We found virus in that material, so it’s not unexpected that some of the avenues we haven’t worked on protecting are now going to be avenues of risk for us today,” he added.

Hollis also urged producers to participate in a PED survey on the www.aasv.org website and to include their premises ID so researchers can know where the virus is and can look at more factors of how it moves.

“We can do a much better job if we know where it’s moving and where we have activity before we get there. Filling out a survey through the (American Association of Swine Veterinarians) website that’s going to ask you about all your different supplies, ingredients, your vet, all these types of things, which help us identify risk so we need that information,” he said.

Hollis applauded the National Pork Board for spending on research and identification of PEDV.

Hollis said a big reason that producers need to help researchers identify where the virus is and where it has been is to prepare for possible future illness events. The virus that has been identified in the U.S., which was first identified in the country in April 2013, is 99 percent similar to a strain found in China.

Hollis said there are currently two strains of the PED virus circulating in the U.S., the second is a less-virulent, less-deadly strain.

“The bad news is whatever brought this virus to us can bring us something else, so that’s why we want to work together and identify how best to prevent it,” he said.