PEDv affects pork industry financially, emotionally
By Jennifer Carrico
Cattle producers remember the cow that stole Christmas when bovine spongiform encephalopathy was found in the United States in 2003. The same could be said about the pig that ruined the year in May 2013 when the first case of porcine epidemic diarrhea virus was confirmed in the U.S.
Over the past year, many pork producers have had to deal with PEDv in one way or another. Most hope it is not because their operation has broken with the virus. Craig Rowles, a partner and general manager of Elite Pork Partnership near Carroll, Iowa, got the call on Nov. 19.
“We had been working hard to keep it out, but sometimes you can do everything right and it still shows up,” said Rowles, who is also a veterinarian.
The operation Rowles manages is an 8,000-sow, farrow-to-finish operation with three sow units, three nurseries and 17 finishing sites. They finish about 150,000 hogs per year. So when the operation broke with PEDv, they knew it would be devastating. The final number of pigs lost was 13,000.
“Outbreak is tough. Mortality rates in a naive herd is 100 percent for 3 to 4 weeks. Our workers were emotionally drained. Many tried to do everything they could to save the piglets that were still alive,” Rowles said. “Unfortunately, many times the baby piglets had to be humanely euthanized. Morale really suffers in an outbreak like this.”
PEDv is caused by a Coronavirus that is related to transmissible gastroenteritis virus. It can only infect pigs and causes severe diarrhea in pigs of all ages, vomiting and high mortality in preweaned pigs. It is thought to have originated from China, but a definite source is uncertain.
Rowles said that when it broke at their operation, they sent fecal samples to Iowa State University for diagnosis.
“At first it looks like TGE, but it didn’t test positive for it, so we had to look further. It was obviously that Coronavirus was present, and then it was a matter of working with other vets internationally to get a definite diagnosis,” Rowles said.
During the spring and summer months of 2013, the virus spread rapidly through North Carolina, Oklahoma and then showed up in the Midwest in the fall and winter months.
Rowles said while they continued to try to prevent the spread of the disease to their other sow sites, on Nov. 28 and Dec. 19, 2013, it showed up at the remaining two sites.
“Our first priority was to manage the pigs that were showing signs of the virus; it was both with animal health and veterinary practices. Exposure of all the animals caused many to die but also built immunity that was needed to prevent further spread of the disease,” Rowles said.
Lisa Becton, director of swine health information and research at the National Pork Board, said the disease is transmitted fecal orally.
“We recommend that producers put in a very strict sanitation protocol. Prevention of transmission of the disease via contact to the feces by other pigs or by clothing or footwear is a must,” Becton said. “Sometimes even with the best sanitation, it will not prevent the virus from spreading.”
In June 2013, the National Pork Board along with veterinarians and producers across the country discussed what all needed to be known about this virus.
“We needed to know the basics of the disease, the epidemiology of it and how long the virus survives in different situations, as well as how it can be spread from farm to farm when no pigs were introduced. By July, research was started to get many of these answers,” Becton said.
By the fall of 2013, many more herds had tested positive for PEDv and more research was needed. Especially needed was research about immunity and how long adult animals pass on immunity, as well as the specific mechanics about how PEDv was being spread from farm to farm.
“There has been over $2 million in research funded since 2013. Some of the initial results are posted online at www.pork.org and new information is coming in and will be shared as soon as we have posted it,” Becton said.
Rowles said they have quit introducing new animals to their operation in hopes that will help prevent new outbreaks and help the current herd to develop an immune response to the disease.
“Our cleaning process is extensive. The amount of virus spread is extraordinary, so the amount of effort to remove is extraordinary as well,” Rowles said. “Cleaning these buildings in the winter months to the extent it is needed was very difficult, but we believe we have now achieved a measure of success.”
Rowles said new testing is being done on the facilities to see if the virus can hide in places such as the farrowing crates even when they are cleaned. Two of their three sow farms have shown success in eradicating the virus, but the third has been more of a chronic problem.
“Sow immunity doesn’t last like it does with TGE. It seems to wear off over time, so we are trying to figure out how to augment the immunity,” Rowles said. “Once the virus is in an area, it seems to put all the herds in that area at risk from outside sources such as boots, feed delivery and supplies.”
Rowles said he is curious to hear the results of research being done on whether the virus can be spread through feed and if it can, how feed processing such as pelleting or heat treatment could help prevent the spread of PEDv.
Becton said there currently isn’t a commercially approved vaccine for PEDv, but several groups and companies are working diligently to find an effective way of prevention.
“Building natural immunity is currently the only prevention method in a herd, and we don’t have a solid answer as to how long the immunity will last,” Becton said. “Clinically some farms have shown immunity for 8 to 10 weeks after an initial PEDv outbreak and then have shown an active infection again. That is what makes this disease so difficult to understand.”
Rowles agreed and said pork producers should not expect a vaccine to be the silver bullet in correcting this problem, as the vaccines developed to prevent TGE were not very effective.
“I don’t expect a vaccine any time soon. Right now, perhaps a new technology breakthrough to enhance the immune response of the sow against the virus would be more effective,” Rowles said.
In other similar diseases, the virus seemed to survive better in colder temperatures, but PEDv seems to not follow that, as it spread through North Carolina and Oklahoma actively during the summer months.
Rowles said the increase in biosecurity and sanitation at the Elite Pork Partnership sites has helped reduce the impact of other diseases that affect their herd as well, such as porcine reproductive and respiratory syndrome.
Becton said it’s hard to know what other diseases are being managed better because of increased sanitation. Since PRRS is not a mandatorily reported disease, it can be hard to track. However, she does know of some research that has shown a reduction or delay in PRRS outbreaks potentially because of the sanitation and biosecurity increase.
The thought of 13,000 dead pigs doesn’t set very well with Rowles. He said it’s a very significant loss both financially and emotionally. However, it does make the pigs that survived worth more.
Steve Meyer, president of Paragon Economics, said the initial reaction of the markets was extreme, but he said the futures are now at a more reasonable amount.
“We have much anticipation for this summer and the impact on hog supply numbers in July,” Meyer said. “I feel that the USDA has underestimated their supply numbers and the third quarter slaughter will be down 10 percent.”
The decrease in supply has driven the prices up. Yearly slaughter numbers are down 7 percent, which also affects export numbers. Meyer said the U.S. will be lucky to stay within 3 percent to 4 percent of exports for the year.
“However, lost quantity leads to record profits. An 18 to 25 percent increase will be seen in market prices this year with prices holding steady in the low- to mid-$120s,” Meyer said.
He said before PEDv became a problem, the hog industry would have likely seen an increase in demand because of high beef prices. However, with the lower hog supply numbers has made the pork prices increase and continue to be supported by the beef prices.
On April 18, Secretary of Agriculture Tom Vilsack announced the effort to further enhance the biosecurity and health of the U.S. swine herd, while maintaining the movement of pigs throughout the country.
“USDA has been working closely with the pork industry and our state and federal partners to solve this problem (PEDv). Together we have established testing protocols, sequenced the virus and are investigating how the virus is transmitted,” said Vilsack in a press release.
Vilsack said the USDA continues to help the pork industry in identifying gaps in biosecurity and spread of the disease. The USDA further will require tracking of movement of pigs, vehicles and other equipment leaving affected premises in hopes of monitoring the surveillance of the disease.
Rowles said it can be difficult to monitor how the disease is spread since 400,000 pigs go to market each day and under 1 million pigs are on the road each day being transferred to market or to nurseries and finishing facilities.
“Everyone is trying to maintain a higher level of biosecurity, but until we fully understand PEDv, the disease will likely continue to linger and reduce production at least through 2015,” Rowles said.
Current information on PEDv and other health concerns can be found at www.pork.org.
Jennifer Carrico can be reached by phone at 515-833-2120 or by email at firstname.lastname@example.org.