Building Biosecurity Boundaries

The Pipestone (MN) Veterinary Clinic has designed its biosecurity programs around keeping out one disease porcine reproductive and respiratory syndrome (PRRS). When Joel Nerem, DVM, was hired by the Pipestone Veterinary Clinic a year ago, he was asked to join six swine-exclusive veterinarians who service 42 sow farms across the Midwest. Nerem was brought in to help upgrade the health management services

The Pipestone (MN) Veterinary Clinic has designed its biosecurity programs around keeping out one disease — porcine reproductive and respiratory syndrome (PRRS).

When Joel Nerem, DVM, was hired by the Pipestone Veterinary Clinic a year ago, he was asked to join six swine-exclusive veterinarians who service 42 sow farms across the Midwest.

Nerem was brought in to help upgrade the health management services that the southwest Minnesota clinic provides for the 120,000-sow Pipestone System.

“Besides servicing approximately 12 sow farms in the Pipestone System, my other role is to coordinate a lot of the health plans that we are doing to make them a little bit more uniform and systematic,” he explains.

“We are applying the best management practices in production, and also creating a more systematic approach to biosecurity for all of the farms that are part of the Pipestone System,” he says.

Nerem is the point person to coordinate biosecurity practices for the growing production system that stretches from Minnesota and South Dakota, down through Nebraska and Iowa, plus one multiplier sow farm in Wisconsin.

The Pipestone Veterinary Clinic provides production management and supervision as well as health services to the sow farms. In turn, the group of small, independent, sow farm owners receive 17- to 20-day-old weaned pigs to finish at their farms.

Biosecurity Challenges

Nerem says the diversity of the production systems presents obvious biosecurity challenges. “You are delivering pigs every week to independent producers with varying health statuses at their farms, and you have to go back into those sow units a couple times a week to get pigs out again, so those activities present a challenge.”

Pipestone swine veterinarians perform regular herd health visits, but biosecurity efforts can easily fall through the cracks as attention is focused on improving production performance, or addressing health challenges, he points out.

“We have a commitment to all of our shareholders to implement the best practices as we understand them for biosecurity. We view that as what is good for ‘this’ farm is good for ‘that’ farm, so that is our approach to making it more systematic across the different sow farms,” Nerem says.

Biosecurity Audits

When it comes to biosecurity, most producers know what needs to be done, but sometimes practices need to be tweaked and producers need to be reminded, Nerem stresses.

That's where Hannah Walkes comes in. The young woman was hired in 2006 as health services technician to focus on streamlining biosecurity practices at the Pipestone System sow farms.

One of her main duties is to conduct biosecurity audits at the sow farms each quarter. “I do random, unannounced biosecurity audits just to make sure people are implementing the techniques that they are supposed to be practicing,” she relates.

Continue Reading about Biosecurity Audits on the Next Page >

The auditing program was instituted when Walkes was hired. “One of the reasons we wanted Hannah on board was because we saw the need to have a consistent process for following up and following through on the implementation of the right biosecurity practices,” says Nerem.

Walkes also explains the science behind biosecurity and why the practices are important to be carried out, he notes.

“So when Hannah makes an unannounced audit, she is there basically to get a snapshot of the farm and how they are doing. This is really a service to the farm manager and to production of the farm,” Nerem stresses.

Walkes admits that farm staff isn't always pleased to see her, especially during that first audit. “I think at first they have a negative opinion of it because of the negative stereotype that an auditor has.”

Despite some early skepticism, she has received some positive feedback. “The biggest comment I have gotten about the audits is that they help keep disease out — so we don't have to deal with sick pigs,” she says. And she has learned a lot from staff about some potential gaps in farm biosecurity.

Decontamination Room

A key addition to biosecurity implemented across the Pipestone System has been the “D&D Room,” which stands for downtime and disinfection, Walkes says.

“People always know that they can track diseases in, and that is why they implement shower-in and shower-out facilities,” she comments. “But what often goes unnoticed are things that you bring into the farm like vaccine products, equipment and other farm supplies.”

That led to a philosophy of a “clean-dirty line,” adds Nerem. Just as there is a clean-dirty line for people showering in and out of a unit, “we need to do the same thing for any of these objects or fomites (inanimate objects) that you are bringing into the farm.”

Rooms or spaces can often be cleaned up and converted into a D&D Room, for example, an old closet or a side office. “We have actually converted old rooms used to house generators and moved the generators outside to make a D&D Room,” he notes.

This concept is not new, but Nerem says Pipestone has instituted some crucial changes. “We have changed the terminology because we really want to emphasize that this is about bringing in items that are physically clean (to start with), and that the focus is really on disinfecting and downtime,” he emphasizes. With their process, items are hand disinfected and then let sit for 24 hours.

“We have moved away from foggers and those kinds of things simply because I think that gives a false sense of security sometimes,” Nerem continues. “The fogger doesn't always get to the bottom of items, whereas, if we are hand-applying, we know that the disinfectant got on everything.”

Walkes says the biosecurity audits also includes a checklist of items to improve on. In the Pipestone System, sow farms must properly maintain:

  • Shower-in and shower-out facilities;

  • Disposal of dead pigs by the end of the day; and

  • A 24-hour downtime policy for visitors. All visitors must receive permission to visit, sign in and indicate their last pig contact.

“We look at overnight downtime for commercial sow farms because we think that a lot of recent research has shown that extended periods of downtime aren't necessary — it is really meant to restrict access,” Nerem observes. Three days of downtime are required for entry into boar studs and multiplier farms.

At each audit, Walkes inquires whether any new employees have been hired. It is company policy that each new worker be educated about bio-security expectations to prevent any lapses in the production system.

Continue Reading about biosecurity testing on Next Page >

Testing Boars, Gilts

The testing protocols for boar studs and replacement gilts are also built around providing safeguards against introduction of the PRRS virus, says Nerem. PRRS can be transmitted very efficiently through semen, so the staff tests for PRRS at the boar stud every collection day. A random sample is sent to the South Dakota state diagnostic laboratory at Brookings, and next-day test results are provided. “The semen cannot enter the clean side of the sow farm until the test results come back negative,” he says.

The gilt-testing program is still being standardized for all sow farms. Basically, gilts are tested for PRRS on arrival, quarantined, and then retested a couple of weeks later. Gilts must test PRRS-negative before entry to the sow farm is permitted.

For most other diseases of concern, clinical signs or herd health history are relied upon to gauge disease status. “In our view, the cost-benefit ratio to testing for a lot of diseases is just not there,” Nerem asserts. “If these were multiplication herds, it would be different. But these are commercial breeding herds, so we are mainly looking at PRRS, and then keeping in close contact with the source herd upstream to make sure that health is good there as well.”

Circovirus is a major health concern. But since it is usually manifested in finishing pigs and not replacement gilts, and most U.S. herds will test positive for the virus, there would be no point in screening incoming stock, he says.

Filtration Technology

Despite intensive biosecurity efforts to keep out the PRRS virus, there are still reports of breaks. But that doesn't mean that every known effort shouldn't be made to keep the virus off farms, says Nerem.

Walkes feels “biosecurity is good insurance and it protects your investments.”

With mounting evidence that aerosol transmission of PRRS is more common than previously thought, Pipestone System installed air filtration systems on boar studs a year ago. So far, none have broken with PRRS. Nerem says after several years of expensive PRRS breaks, there has been a “huge movement within the boar stud community to get these studs filtered.”

Air filtration systems are being seriously looked at for commercial sow farms within the Pipestone System, too, he adds. None are filtered at this time.

Transportation Improvements

“What we once thought was a clean trailer wasn't really clean — it was partially clean,” Nerem says. “First hand, we sampled some trailers that had been through a truck wash and found infectious PRRS virus on the trailers a day after washing. We were able to get test samples for PRRS and actually infect pigs with those samples.”

To prevent that scenario from re-occurring and provide another layer of biosecurity, the Pipestone System is planning to build a new, two-bay truck wash this summer to allow proper washing and disinfecting of trailers, Nerem remarks. It will replace the current single-bay truck wash. Sow farms in other areas contract with commercial truck washes approved by Pipestone veterinarians.

Another new feature coming soon is a trailer audit, Walkes says, to make sure trailers are cleaned and disinfected according to specifications.

“I'm not sure this is really anything new. Other systems have done it, but we have made an expectation of the level of sanitation at both the truck wash and in a trailer before it goes back to the farm. Now, we are following up to make sure that standard is being met,” Nerem reports.

Walkes will also be responsible for randomly auditing trailers, much as she does for the sow farms. “If the truck and trailer are not kept clean, then everything that you do at the sow farm (for biosecurity) is kind of useless,” she states.

To minimize the biosecurity risk of a potential disease transmission, a trailer is dedicated to each sow farm. Nerem believes this step, along with good sanitation and disinfection, will alleviate much of the risk of transportation and the need for expensive drying technology.

Good Biosecurity

A system that provides good biosecurity protects animal health, animal welfare and maintains positive morale of staff, while also reducing the cost of biosecurity to the production system, Nerem suggests.

Biosecurity must be made a higher priority in order to safeguard the swine industry from PRRS and circovirus, he adds.

To achieve success against these two serious pathogens will require improved communication and disease-monitoring strategies, using regional efforts guided by computer-aided, disease-mapping technology, Nerem says.

“It will really require a higher level of cooperation than what we have done in the past, including a willingness to share information about what is happening on producers' farms as far as disease status in order to achieve the overall benefit of getting rid of certain diseases, before they become epidemics. We need to look at how we cooperate, coordinate and communicate,” he concludes.