Needles & Sins: Sloppy vaccination protocols can jeopardize herd health, welfare, returns
Innocent but often costly mistakes happen when vaccines aren’t properly stored, handled or administered. Pig Health Today talked with an Illinois producer who lost 30 market hogs following a vaccination slip-up. We also checked in with the producer’s veterinarian and three other experts about what producers can do to get the most out of their vaccination investment.
Sloppy vaccination protocols can jeopardize herd health, welfare and returns
Nick Zanger learned a few tough lessons about vaccine protocols shortly after he started managing three 2,500-head nursery-to-finishing buildings near Loraine, Illinois.
He and another worker were vaccinating a barn full of pigs. Halfway through, Zanger realized his worker’s syringe had malfunctioned and was not injecting vaccine. He had no idea when the syringe quit because it was a hose-style, draw-off syringe with the vaccine bottle hanging over his head. They had no choice but to start over.
“It cost us 4 hours of work, plus the extra vaccine,” he says. “After that, we went to bottles mounted on top of the syringe so we could see the bottle draw down as we gave shots.”
Innocent mistakes also can happen when vaccines aren’t properly stored, Zanger says. He recalls receiving a shipment of vaccine packed on dry ice. Not being familiar with the vaccine, he unpacked it and put the vaccine in the freezer. When it was time to vaccinate, he thawed the vaccine and ran it through the water medicator in the building for 6 hours.
Lost 30 market hogs
“Several weeks later, we had an outbreak and lost 30 market hogs,” Zanger says. “It was during the summer and real hot, so we were dragging out 250-pound pigs in the heat.”
After the outbreak, Zanger said a group, including the owner of the hogs, got together with him to discuss what happened. They decided the cause was either vaccine mishandling (including putting it in the freezer), or not all the pigs drank the medicated water.
Armed with considerable respect for vaccines, Zanger now precisely follows all immunization protocols and remains diligent about making sure all pigs are vaccinated.
“This has changed my attitude about vaccines,” he says. “It validates that vaccines are necessary for the health of pigs.”
Zanger’s new commitment to proper vaccination techniques is critical for keeping hogs healthy and profitable. Well-trained employees — those who understand the responsibilities at hand — are the ones who become sticklers for detail and excel at the difficult task of vaccinating hundreds of pigs a day.
New pork industry efforts are now underway to address some of the shortfalls in vaccine handling and to improve caregiver training. These initiatives will become even more important as veterinarians and producers lean more on vaccinations for managing disease.
Cost of unprotected pigs
“Improper vaccinations will eat up profits quickly,” reports Bill Hollis, DVM, Carthage Veterinary Services.
“What we have learned over the years in both pig-health management and immunity management of disease is the incredible value of proper immunization.”
Anyone who doubts this should think back to the circovirus outbreak that hit 10 years ago. “Some hog farms lost 25% of their population,” Hollis says. “That was a massive loss. Properly vaccinated pigs now cut overall wean-to-market mortality down to 3% to 5%. That’s a big change.”
The experienced vet from Carthage, Illinois, has watched vaccines improve over the years. “ Animal-health pharmaceutical companies have created products that are more flexible, so we can often combine them, and they last longer,” Hollis says, referring to expiration dates on today’s commercial vaccines. “ Twenty years ago, there were some harsh vaccine products and adjuvants that had a significant impact on pigs.”
Attention to vaccine protocols has improved too, according to Derald Holtkamp, DVM, Iowa State University (ISU).
“Both veterinarians and producers pay more attention to protocols. It’s not perfect, but it has gotten better. We need to learn how to better manage the immunity of the pig because, over time, we will have fewer antimicrobials to fall back on.”
Even with more attention to protocols, problems still exist with vaccine handling. “I’ve seen bottles of vaccine sitting around for a long time with a needle in the top,” Holtkamp says. “I’ve seen out-of-date vaccines, vaccines not refrigerated and syringes cleaned with a disinfectant that kills the microbe in a modified-live vaccine.”
Then there are the problems that occur during vaccination. “You can inject a pig with a syringe and not give a full dose,” Holtkamp continues. “At the end when you do an accounting, not all of the vaccine has been used.”
While some large hog units hire specialized vaccination crews, Holtkamp has reservations about that approach.
“These crews are frequently paid by the pig or by the group of pigs, so they move very quickly,” he says. “Can we afford to pay them for speed only? They usually get most of the pigs vaccinated because they are marked, but it may not be the full dose or in the right location. Some companies are looking at other ways to pay them.”
Zanger can attest to the sheer difficulty of administering shots to hundreds of pigs in a day.
“Giving shots is not fun. It’s usually 78° F to 80° F, so you are sweating with pigs stepping on your feet and squealing,” he explains. “You bend over all day to vaccinate pigs that aren’t a foot tall. I can see where someone may think half a job is good enough. But I’d rather spend a day giving shots than spend a month pulling out dead hogs.” In the past, vaccinations were often given by the individuals who owned the pigs, according to Micah Jansen, DVM, a technical services veterinarian with Zoetis. Now the caregivers working with pigs every day often do not own the pigs.
“It might be challenging for owners to understand why employees don’t have a desire to do a good job vaccinating,” Jansen says. “But, if an employee can’t see a direct, positive impact to them for proper vaccination, it can be hard for them to want to do a good job vaccinating.
“Often the task of vaccination is assigned to people who are not familiar with the how and why of vaccines,” she adds. “So, there’s a lot of room for improvement in how we educate employees who administer vaccines.”
The practice of cutting dose rates — using a half dose as a cost-saving measure, for example — or taking other shortcuts not indicated on the vaccine’s label presents another issue.
“I understand why producers want to do it,” ISU’s Holtkamp says. “But it is risky and very difficult to justify, because there is very little research on cutting doses.
“You are always on thin ice,” he adds. “And once you are off label, you are on your own.”
The vaccine’s efficacy and safety data generated by an animalhealth company to secure licensure from USDA is based on a full dose. The full dose delivers the correct amount of antigen to the pig to create the proper immune response, Jansen explains. A partial dose obviously does not and is risky to use. While producers can easily calculate their savings from partial doses across thousands of pigs, they can’t predict a disease challenge and the cost of lost production.
“If you are not vaccinating to the potential of the vaccine, then you allow the virus or pathogen to stay in the group of pigs for a long time; it will eventually cause disease,” warns Darin Madson, DVM, ISU pathologist.
“The biggest problem is not getting adequate protection so we can clear the virus,” he continues. “It allows the pathogen to stay there until pigs are bigger and worth more money and then get sick.”
When a pathogen lingers, Madson explains, the herd’s rate of gain often drops because the pigs spend more time in the building and consume more feed over time. “The pathogen is hanging out and causing subclinical disease,” Madson adds.
How to improve vaccinations
What’s the long-term solution for improving the success rate of vaccination programs?
“Since vaccines will always be standard equipment, it comes down to the people and processes that make the biggest impact,” Madson says. “Do we have the people who take time to put the needle in right? We need to help people be successful vaccinating the pig. So for me, it’s about education to make sure we are doing this correctly.” Employees are now being trained on vaccination protocols and, in some cases, with help from veterinary services. For example, the Carthage system has an educational facility where clients’ employees learn about vaccinations and why the protocols are required.
“We have these large groups of producers and employees who do not understand how vaccine products work,” Hollis says. “And they don’t provide the proper equipment. That’s why we’ve chosen to focus on the tools, the vaccines and an understanding of the disease process.”
The animal-health company, Zoetis, is taking a more active role in ensuring the proper use of vaccines. Jansen helped develop the Vaccinologist Program by Zoetis, designed not only to train pig caregivers on vaccinations but also educate them about how vaccines work (See sidebar).
Most important job
“The best way to get around the vaccination problem is to improve the mindset of the caregivers who will actually be doing the vaccinations,” Jansen explains.
“They have to understand how important their role is and how very important it is in the process of raising pigs.
“Vaccinating pigs is not just something assigned to the low-level employees. They have to know that we place value on what they are doing,” she adds.
Madson echoes that sentiment. “It’s hard work and not the most glorious work,” he states. “But it’s one of the most important jobs done to that pig.”
Future vaccines rely on other pathways for delivery
Posted on October 19, 2018