‘Doc, what should I vaccinate my pigs for?’

One of the most common questions Daniel Brown, DVM, hears from swine clients is what vaccinations are needed and when should they be given. “That topic seems to come up on almost every farm visit,” he said. Brown works from the Four Star Veterinary Service clinic in Holland, Michigan.

Ultimately, the goal of any vaccination strategy is to help lessen the risk of a disease challenge that will adversely affect pig production.

“The hope with any vaccine is, by exposing the pigs to a bug or even a piece of a bug, that their bodies learn how to deal with the pathogen if they come across it in the barn,” Brown explained. “Sometimes, we are trying to protect the pigs from a bug we know they will see, and other times, we are trying to give them protection from a bug they might see.”

Type of hog operation

Several factors can influence the vaccine strategy a veterinarian develops for a hog farm. The first and most important one is the type and objective of the hog operation.

“In the Four Star group, we work with a range of clients from large commercial producers focused on producing pounds of quality pork to families focused on raising a handful of good-looking pigs for the show ring,” Brown said.

The different objectives of each client’s hog operation are kept in mind when developing and implementing vaccine strategies.

Health history, pig density, logistics

Veterinarians also consider other health challenges the farm has battled and pig density when building a vaccine program. Clients located in pig-dense areas generally have faced more disease challenges than clients in locations such as the upper peninsula of Michigan.

And then there is the issue of logistics on the farm. “Vaccine protocols developed by veterinarians consider how the pigs are going to be vaccinated so it will be followed,” Brown said. “It is imperative that everyone understands and agrees on the strategy to be implemented.”

Common vaccines

One of the most common pathogens requiring a vaccination is porcine circovirus type 2 (PCV2). Brown includes a vaccine strategy for PCV2 on virtually all farms “because it is so widespread and can have a wide range of effects from increased mortality in nurseries to reproductive failure in sows.”

Another set of bugs that are frequently vaccinated for in combination are parvovirus, erysipelas and several types of Leptospira. Often times, this will be seen in breeding animals to help prevent reproductive failures.

Other bugs that are vaccinated against will often be farm specific and may vary on what coverage can be achieved with a single product. For instance, PCV2 vaccines are often combined to include coverage against Mycoplasma hyopneumoniae.

If other vaccines such as erysipelas or influenza are added into breeding and/or market-hog protocols depends on factors such as pig density in the area and how previous groups performed.

“I’ve seen mild flare-ups of erysipelas in finishing stages and have had to add in a dose after weaning,” Brown said. “It’s definitely something that’s still out there and can be seen in groups that come from sows vaccinated against it.”

Many vaccination programs will include protection against influenza. “Flu travels around very easily, and we can often see a new strain develop like we see in humans,” Brown said. “When we vaccinate for the flu, it helps to reduce signs and symptoms. I will often lean heavily on using a flu vaccine in pig-dense areas.”

Show-pig vaccinations

Brown’s vaccination strategy for most show pigs tends to be more proactive than in commercial settings where biosecurity is typically stronger.

“In the show world, it’s a larger challenge to have a robust biosecurity plan, as well as a successful breeding and show operation,” he said. “Quite often, clients will use gilts and boars that were successful on a show circuit to replace their breeding stock.

“At a show, they may go to a barn with 750 pigs that came from 500 different farms,” he added. “In these cases, I start talking about a robust vaccine program that includes all of the vaccines mentioned above (PCV2, Mycoplasma, influenza, erysipelas, parvovirus and Leptospira) plus more, depending on those other factors such as previous herd health.”

Vaccine follow-up

Brown’s goal when setting up a vaccine protocol for any client is to decide what diseases the pigs need to be protected against and what’s the best way to do it. Equally important is following up with the client to see how the strategy worked and if it needs changing.

“Vaccinology” is a huge topic of discussion and for good reason. Vaccines allow for sows to continue producing litters of healthy pigs, for market hogs to continue producing quality pork, and for youth to show their healthy animals in competitions.

“As veterinarians, providing vaccine protocols is just one piece of the puzzle,” he said. “We must also strive to make sure clients understand the importance of following those protocols and why we developed them. If clients know the ‘why’ of protocols, then they will often be more successful in the implementation of the strategies,” he concluded.

“We need to have a conversation on why each vaccine is important and why the timing is important. If you take the time to explain the ‘why’ to clients, then we will often be more successful in the implementation of our strategies,” he concluded.

Develop replacement heifers like a cow but with exceptions

Cow-calf herds can add a nice profit to the bottom line of hog production systems that use manure on their own pastures. These profits can increase long term if herds keep and develop their own replacement heifers, suggests Harrison Dudley, DVM, Four Star Veterinary Service in Kinston, North Carolina.

“When we make a decision to keep a heifer, we are taking $750 to $1,000 off the income list in the short term,” Dudley said. “But the benefits in the long term outweigh the costs upfront. And it is a very long-term benefit.”

Selecting heifers

One big benefit of selecting replacement heifers from your own herd is you know the genetics, and they work in your system, he explained. Plus, you can continue to make herd improvement through your bull selections.

When developing heifer replacements, Dudley recommends a heifer “stress test.” The stress test involves moving heifers to a pasture to see how they perform but keeping them separate from the cow herd.

“The stress test is to treat a heifer like a cow,” he said. “A lot of folks baby the heifers to get them pregnant and deliver their first calf as quickly as possible, which is important. But I think that artificially selects animals that can’t handle the stress as a cow, where they are put into a pasture with 100 other cows and have to compete for resources.”

Keep heifers separate

Ideally, Dudley still wants replacement heifers separated from cows but kept in pastures dedicated to heifer development. Here the heifers are provided supplemental nutrition to help them continue growing.

“I don’t think a heifer can do it on grass alone,” he said. “They need to be on a good, chelated mineral that is balanced for our part of the world, and not the generic feed-company blend.

“I like them to get some protein and energy supplementation at 0.5% bodyweight up to 1% of bodyweight to keep them growing so they can have a calf by the time they are 2 years old.”

Dudley recommends trying to get heifers bred by the time they are 15 months old. Anything earlier is too young, he adds, because the heifers are still growing.

Heifer development not easy

“A heifer is a different animal than a cow,” Dudley said. “Most cow-calf producers are really good cow managers but not good at heifer management.”

“I have one client with a herd of 80 cows that are 15 years old. They keep their own heifers. It’s nothing fancy, but it is efficient. They’ve made mistakes, but it’s designed well and it performs.”

Producers looking for help with selecting and developing replacement heifers should contact their local veterinarian or Dudley at hdudley@livestockvet.com.


Early identification critical in preventing sow lameness

Sow lameness continues to trouble hog operations in the US, causing high numbers of involuntary removals from herds. These expensive sow removals can be reduced by identifying lameness issues early and addressing equipment hazards that lead to sow injuries, reported Michael Pierdon, VMD, Four Star Veterinary Service, Elizabethtown, Pennsylvania.

“When a sow develops lameness that is severe enough that she is no longer able to get to the feeder…she will need to be removed regardless of her age or production history or stage of gestation,” Pierdon added. “Those involuntary removals are really damaging financially to sow herds.”

Identify gait issues early

Injury to the hoof and foot cause most lameness that eventually leads to removals. Pierdon said these injuries can go unnoticed by farm staff because pigs are good at hiding them.

“Those injuries can become infected, and the infection festers and becomes more severe over time, eventually causing significant damage within the joint, bones or foot,” he said.

“Once the damage progresses to that point, the animals aren’t recoverable. Medically we’re just not able to manage them back to health.”

The key to preventing this scenario is training farm workers to identify animals much earlier in the course of the disease.

“We need to identify animals when they have a gait abnormality or are not walking smoothly,” Pierdon explained.

“Aggressive antibiotic treatment strategies can have some success in resolving these issues before they develop into a [high] level of severity.”

If farm workers wait to treat an animal until it is unwilling to put weight on a leg, it is too late. Clinically resolving lameness at this point is very unlikely.

Pen-gestation hazards

“Lameness has really risen in importance as we’ve begun to house sows more often in group-housing situations,” Pierdon added. “An animal needs to be able to move and move effectively without pain to compete and thrive in a group environment.”

The move to group housing offers more opportunities for sows to move around, interact with other sows and become injured, which begins the lameness process, he explained.

In addition, many sow barns are equipped with slatted flooring designed for stall gestation. When converted to pens, the slats are too wide for sows to walk on, and injuries occur when feet get stuck in the slat gaps.

Pierdon said he also has seen injuries due to hardware issues, like sharp edges sticking out of the floor or feeders facing the wrong direction.

In barns where the facility issues were fixed, the number of lameness issues improved, he added.

Genetic improvements

Compounding the lameness issue are sow genetics that haven’t focused on traits needed for pen gestation.

“Animals with heavier bones, with bigger feet, will likely do better as far as lameness goes,” he said. “We really need help from our genetic partners on that, on selecting for traits that ensure soundness and survivability in these housing systems.”

While lameness will never be fully solved, Pierdon believes the industry will learn to manage it better.

“The biggest drivers will be facility design and genetic improvement, refocusing on structure and durability on the genetic side,” he said. “But also continuing to experiment and study facility design to find options that reduce the risk of injury to the animals.”

In the meantime, attention to the first signs of lameness will help farms better handle sow injuries and lower involuntary removals from the herd.