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.



Strategies to curtail rising sow-lameness problems

Sow-lameness issues are on the rise, especially for sows in group housing, according to Michael Pierdon, VMD, Four Star Veterinary Service. Lameness is a leading reason that sows are culled early from the herd.

“Sow lameness is not a new problem, but it has come into focus as sows are moved into pen gestation,” Pierdon explained. “Structural soundness is much more important in a loose-housing environment than in a stall environment. They really need to be sound in order to survive in the herd.”

He sees other causes of sow lameness, too, including inadequate gilt nutrition, pen hazards leading to injuries and delayed identification of lameness.

Located in Elizabethtown, Pennsylvania, Pierdon works with many hog producers who house gestating sows in pens. He employs four management strategies to address sow lameness and reduce the number of involuntary removals from herds.

1. Structural soundness

Preventing lameness starts with gilt selection. “Make sure you get animals with structural soundness and integrity because poor structure will lead to lameness quickly,” he said.

Unfortunately, genetics companies have not been forced to focus on leg and foot soundness since sows moved into gestation stalls 30 years ago. Pierdon hopes that changes, and there’s a renewed focus on sows with bigger feet and bone structure to handle the rigors of pens.

“Once you establish proper structure and good gilt selection, then you must develop the gilt properly to ensure she meets her genetic potential, and that’s largely done through nutrition,” he continued. “She must have the nutritional program that supports bone and hoof health, or we predispose her to lameness issues.”

2. Reduce injuries

Injury is a leading cause of sow lameness, Pierdon said. Most of the injuries are to the foot and hoof.

“We are learning that a significant amount of lameness is due to ascending infections from damage to feet and breaks in the hoof wall that get infected,” he said. “If that infection isn’t identified early, it has the chance to spread deeper into the tissue and joints and ultimately becomes an unresolvable issue.”

Poor equipment design increases the chance of sow injury.

“Sow barns built for gestation stalls typically have a pretty wide slat gap,” Pierdon said. “But when the sows must move around on those floors when the barns convert to group housing, the gap is wide enough that a sow can get her toes stuck and damage her hoof. We need to continue to work toward smaller gaps or another type of flooring.

“We also see a lot of gating and feeders that are fastened to the floor with bolts sticking up and sharp edges all in the path of feet. Anything that can be stepped on and cause foot injuries are what we really worry about,” he added.

3. Identify lameness early

One key to reducing lameness is detecting it early before the problem progresses to the point it can’t be resolved. This can be difficult.

“Sows are tough and will hide or manage to survive with their lameness for quite some time until it becomes really severe,” Pierdon said. “If you gauge lameness by the sows not eating that day, then it is too late. By the time they can’t get to the feeder, their lameness is so advanced that the likelihood of resolving it is minimal.”

He recommends evaluating sows daily to watch their gaits and look for any sign of lameness like unsteadiness, shifting weight or gingerly tapping feet on the floor. Waiting for sows to progress to three-leg lameness is too late to identify the problem and expect recovery.

“Workers have to be very attentive to the animals,” he explained. “They have to really watch sows stand and move in order to identify lameness.”

4. Proactive treatment

“Workers also have to err of the side of aggressive treatment,” he continued. “They need to be proactive if they want a chance to resolve these issues.

“A lot of people do not realize how severe the damage is by the time they identify it and start treating these animals. Workers get frustrated because they try to treat lame animals and it doesn’t work. Sows must be identified and treated way earlier in the course of the lameness issue.”

Treatment options depend on the severity and type of lameness. Pierdon recommends working with a veterinarian to determine the best treatment protocols.

“Lowering sow lameness often has to be a multifaceted approach,” he added. “It’s a real challenging issue when sows are housed in pens.

“Success to me is keeping lameness at a manageable level and maintaining normal removal rates. It also is giving the crew wins where they feel like they have some power to influence this issue and reduce the number of animals they identify as lame.”


Check with your Four Star veterinarian to investigate sow lameness at your farm.



Raising pigs without antibiotics offers niche market but with limitations



Markets for pork produced without antibiotics continue to grow. But this method of production is not for every farm, cautions Michael Pierdon, VMD, veterinarian with Four Star Veterinary Service, Elizabethtown, Pennsylvania.

“A lot of clients do ask questions about it…They see it as a business opportunity,” Pierdon said. “But first of all, is your herd really a good candidate? Meaning, what’s your disease profile? Is your current pig-farm setup and pig flow appropriate for antibiotic free or would you have to consider reworking that in order to have good success?”

Additional costs

Producers interested in this method of pork production should expect higher production costs.

“Often producers ask about it because they’ve been offered more money for their pigs if they create antibiotic-free pigs,” Pierdon said. “Creating those pigs will also cost more money because there’s more cost in vaccines, facilities, some inefficiencies in flow, and other demands nutritionally that are going to be required.”

In some cases, the expected premium evaporates with the higher cost of production.

Being profitable

Pierdon works with many producers who stay profitable in this niche market. But it’s not just about profits for them.

“Especially for smaller operations and owner/operators, this is a niche that they can get into that finds them a home in the modern industry,” he explained. “They’re able to do something that may be a little more intensive than the bigger players.”

The keys to success start with what Pierdon calls a “multi-faceted approach,” starting with good, healthy breeding stock to minimize endemic disease. This helps baby pigs start healthy, free of disease and able to fight off minor health challenges on their own.

The proper environment and management also are required to keep the pigs as healthy as possible throughout their lives. Pierdon maintains that all-in, all-out production gives producers an edge when antibiotics are not available.

“All-in, all-out gives you the ability to eradicate disease when it happens,” he explained. “Sometime the animals will become sick, and when you have all-in, all-out, you never have to have the disease for more than one group of pigs.”

Ventilation and temperature controls must be correct. Feed and water systems must work properly.

“All those things contribute to animal health by increasing or decreasing stress,” Pierdon said. “Managing the environment really helps, especially with what I call the standard bacterial diseases…If you can put pigs in the right environment, they have a lot better chance of resisting those challenges.”

Vaccinations important

Producers raising pigs without antibiotics need vaccinations to control many disease challenges or pathogens.

“We probably use more vaccine technology in antibiotic-free production because that’s one of the biggest tools in the toolbox,” Pierdon said. “And without the ability to treat disease when it occurs, prevention is just a lot more important.

“For instance, ileitis is a disease that can be controlled effectively through medication in the feed in commercial flows,” he continued. “But in antibiotic-free production, you’ve really got to use vaccines to control it.”

Growing demand

Pierdon expects consumer demand for all types of pork production without the use of antibiotics will continue to grow. These include niche markets that also add housing, nutritional and management restrictions.

“Increasingly, big purchasers of commercial pork in the US will want [pork] to be produced without antibiotics,” he said. “As we transition more and more of our commercial industry today to that, we need to embrace and develop new technologies that will allow us to manage the health of the animals without antibiotics.”


8 key factors drive success when raising pigs without antibiotics

A cluster of hog farms raising pigs without antibiotics developed in southeast Pennsylvania where hog operations tend to be small and expansion limited. The producers here recognized that this was a way to stay viable raising hogs without getting bigger.

Helping many of these operations make the switch to producing hogs without antibiotics is Michael Pierdon, VMD, veterinarian with Four Star Veterinary Service, Elizabethtown, Pennsylvania.

Pierdon says the decision to enter into hog production without the use of antibiotics should not be made lightly. Producers need to recognize there will always be health challenges. The goal is to resolve those challenges as they arise and not let them become a “gradual increase of endemic disease that makes antibiotic-free production untenable,” he added.

Based on his experiences, Pierdon recommends eight key factors that drive success in hog production when not using antibiotics.

1. High health status

Breeding stock and pig flow should be negative for these diseases: porcine reproductive and respiratory syndrome virus, porcine epidemic diarrhea virus/porcine delta coronavirus, actinobacillus pleuropneumonia and swine dysentery.

Other disease such as Mycoplasma hyopneumoniae (M. hyo) and influenza A (IAV) are ideally excluded from pig flow but are more easily managed with vaccination than other diseases.

2. Strict biosecurity

Excellent biosecurity is needed to prevent disease introduction.  If the most severe diseases are kept out, other endemic diseases are more easily managed through a combination of appropriate gilt acclimation, vaccination protocol, pig flow and husbandry.

3. Gilt acclimation

When possible, use replacement stock from the same source used to originally populate the barn.

Gilt facilities on breeding farms should allow a 2- to 4-month acclimation period when diseases like IAV and M. hyo are present.

Internal development of replacement animals is a good way to manage exposure and acclimation of replacement stock, as long as external disease introduction is minimized.

4. Vaccination

A vaccination program that creates a diverse, robust immunity is key to preventing the emergence of disease. Vaccinations should address all endemic diseases present in the breeding herd and pig flow, as well as diseases that the pigs will likely encounter downstream.

Breeding herd vaccinations should include porcine circovirus type 2 (PCV2), M. hyo, influenza, parvovirus/leptospirosis/erysipelas, Haemophilus parasuis and Salmonella.

Growing pigs should be vaccinated against PCV2 and M. hyo along with ileitis. Additional vaccinations frequently are necessary to control Salmonella, E. coli, erysipelas, Pasteurella/Bordetella and IAV.

Vaccination protocols should maximize immune response. This means vaccinating at the correct age with full doses and using two-dose protocols when necessary and recommended.

5. All-in, all-out pig flow

Pierdon suggests using batch farrowing on sow farms and all-in, all-out pig flows on grow-out sites to allow the elimination of diseases that emerge in the normal course of production.

Large populations impact health, too. He recommends setting up systems to minimize the number of pigs at one site without sacrificing the economies of scale needed to be sustainable.

He recommends keeping sow farms at 1,400 head or less and on a 4- or 5-week batch system with each group flowing to distinct grow-out sites that are emptied after each turn.

6. Barns designed for comfort

Barns used for raising pigs without antibiotics must allow for optimal husbandry conditions. Proper ventilation and temperature regulation are critical in preventing environmental stressors that can predispose pigs to disease.

Use zone heating, mats, hovers, etc., to manage the microenvironment for pig comfort. Water systems should allow routine use of oral vaccines and supplements. Water treatment systems may be needed in some areas to control pH and bacteria.

Smaller, conventional penning with 20 to 30 pigs per pen is better than large pen designs.

In hospital pens, create a separate drinking system to provide oral antibiotic treatment. An individual, moveable, gate-mounted, gravity-fed drinking system is recommended.

7. Producer engagement

“Producer engagement is key to the success of the growing pigs, particularly in the nursery phase,” Pierdon said. “Careful attention to requirements for environmental management and for individual pig care are required in order to optimize success.”

He also recommends making the training of animal caretakers take high priority. The time and resources invested in training will help keep caretakers engaged and motivated.

8. Veterinary oversight

Veterinarians have a key role to play in hog systems not using antibiotics. “Prompt, accurate diagnosis of disease challenges and timely, targeted treatment can often prevent the need for mass medication,” Pierdon said.

“Responsibility for this oversight cannot rely on lay staff,” he added. “Veterinarians have training and expertise that allows them to view the ‘big picture’ and identify not just the disease challenges present but also the factors that predispose those diseases.”

In addition, regular veterinary visits to the production sites help ensure proper medical care of all animals when necessary.

“Our responsibility is to advocate for the animals under our care,” he explained. “This includes promptly initiating antibiotic treatment when necessary and broadly enough to prevent disease outbreaks that compromise animal welfare.”