Page 12 - April 2018
P. 12

SFMCA FeedSafe Accredited
New forms of swine influenza pose challenges to US herd
Soya beans used in our meals are NOT genetically modified! CONTACT:
NEW strains of the swine influenza virus continue to emerge, making it difficult for pork producers to man- age, two experts who specialise in the disease of food animals said at a recent webinar organ- ised by Farm Journal’s PORK.
The webinar ‘Swine in- fluenza and what it means to you’ featured two pan- ellists: Marie Culhane, DVM, an associate pro- fessor in the Department of Population Veterinary Medicine, University of Minnesota; and Micah Jansen, DVM, a swine technical services veteri- narian for Zoetis who has worked extensively with the disease in the field.
In the hour-long ses- sion, the two experts said despite the changing na- ture of this deadly virus, producers can work with
veterinarians to prevent or manage outbreaks by monitoring influenza sur- veillance data, vaccinat- ing pigs and stepping up and enforcing biosecurity protocols.
Looking back
Like many diseases, in- fluenza has been around for centuries.
However, it didn’t attract much global attention un- til the 1918 flu epidemic, which is estimated to have infected more than 500 million people, or one- third of the earth’s pop- ulation at the time, and killed between 20 million and 50 million, according to the National Institutes of Health.
Using advanced tech- niques, Culhane said sci- entists have determined that the 1918 virus was of the H1N1 variety that got into humans and swine at the same time.
That H1N1 virus evolved in swine and was stable for 70 years.
But over time, a strain of the influenza virus, known as H3N2, was transmitted from humans to swine.
“What happened around 1997 was that H3N2 got into swine,” Culhane said.
“What emerged was this triple re-assortment (referring to the mixing of genetic material of one influenza genotype into new and distinct combi- nations).
“Since then, the world of this virus has been inter- esting for swine.
“Another big outbreak occurred in 2003, but this transmission was from swine to swine.” Evolvingvirus
The experts say this con- tinuous emergence of new viruses is one of the biggest threats to pig farmers.
“It’s difficult for produc- ers and even veterinarians to keep up with all the changes,” Jansen said.
“So, I think the key thing for producers is to work continuously with their veterinarian to help them understand what is circulating within their herd and figure out what’s best for their situ- ation.”
Culhane said there are no new vaccination tools to combat some of these emerging viruses in a timely manner.
Furthermore, it can take nine months or more for animal health compa- nies to add or substitute a strain without conduct- ing full-scale efficacy and safety studies under USDA’s Expedited Strain Change guidelines.
The two offered a va- riety of suggestions for staying ahead of and con- taining the influenza vi- rus in swine.
Among them:
1. Make sure workers and others who come in contact with the animals understand the impor- tance of following bio- security measures.
“One of the factors that drives influenza change is continuous introduction of virus from humans into pigs and how that changes influenza viruses in pigs,” Culhane said.
“We want to not just vaccinate pigs but have good biosecurity pro- tocols, such as wearing gloves and masks when working with pigs.”
Jansen said the key to getting caregivers to buy into these protocols fas- tidiously is getting them to understand why.
“There’s a good reason for what we ask them to do, but sometimes care- givers may not get the back story,” she said, re- ferring to both the eco- nomic and pathogenic ramifications of lax bio- security.
“When you help them understand the why, they are more passionate about it and care more.”
2. Study the data on
swine influenza scrupu- lously.
Although influenza pos- es a year-round threat to swine herds, peak season is in winter.
“It is important to look at multiple streams of sur- veillance data,” Culhane said.
“You could have any one of these viruses at any time in the US.”
The USDA maintains a National Swine Influenza Surveillance Program.
The program compiles results quarterly and the influenza data is broken down by geographic re- gions.
There are five regions in all and the data varies by region.
“The most common virus in 2017 was the human-like, seasonal H3 that is passed from pig to pig,” Culhane said.
“The next most common were 4a and 4b.”
3. Adopt smart vaccina- tion strategies.
Vaccine use is still ad- vantageous for sow farms. As of last October, there were only two fully li- censed, commercial vac- cines for swine influenza available to US pork pro-
However, five compa-
nies produce autogenous vaccines and three more are looking to produce them.
Studies show sow vacci- nation and the gilts’ influ- enza status at entry often determined the likelihood of influenza at weaning.
Vaccinating a sow stim- ulates maternal-derived antibodies, or MDAs, which help protect piglets.
Another strategy is to vaccinate growing pigs.
Culhane said MDAs wane by four weeks and studies show sow vaccina- tion decreases the likeli- hood of influenza in pig- lets at weaning.
“Vaccinated sow farms are less likely to have in- fluenza A-positive piglets at weaning,” Jansen said.
“Influenza is unpredict- able, so you need a vac- cine that will give broad coverage.”
Bennie St, Industrial Estate, Dalby
Ph (07) 4662 4333
A/Hrs (07) 4663 5534
We use whole soya beans not gradings to supply you with a quality meal
Excellent quality Concrete Slats for Piggeries
  Farrowing and weaner crates, growers and baconer pens.   Feed hopper with stainless steel trough.
See us at the Pan Pacific Pork Expo – May 30-31 | STAND 58
  Farrowing flooring with a 10mm gap; weaners flooring with a 12mm gap; and growers flooring with a 15mm gap.
Diagonal Farrowing Crate. Straight Farrowing Crate.
Ph (02) 6644 6065
Mobile 0437 431 901 | Email
2 Clark Rd, Junction Hill • PO Box 421, Grafton NSW 2460
Head Office:
Victoria: Freecall:
Vereyken Bros. Pty Ltd ABN 11 003 543 548
Ben Slots 1800 999 245
Anytime or (02) 6644 6065 Mobile: 0437 431 901
Phone: (03) 9462 4266 Mobile: 0418 388 842
Page 12 – Australian Pork Newspaper, April 2018

   10   11   12   13   14