Sometimes the best opportunities come from looking at common areas in a new way. Such is the case with sow health. This production phase is often relegated to simply achieving more pigs per sow per year or reducing non-productive days. However, today the industry is reexamining the health role of the sow in broader terms, searching for new ways to leverage it to produce more full-value pigs all the way to market.

That’s exactly what happened last spring on Terry Weisheit’s farrow-to-finish operation in Petersburg, Ind. He had noticed persistent coughing in many of his 16-day-old nursing piglets and contacted his veterinarian, John Baker, DVM, Boonville, Ind. Weisheit was confident that the immediate problem could be solved. However, he didn’t realize that this health challenge would lead him down a path to improving overall herd health and performance by focusing on the sow herd.

“We were able to quickly confirm the presence of multiple respiratory pathogens including Pasteurella multocida,” Baker says. “So we decided to use an in-feed treatment in the sows’ lactation diet because we’ve had good experience with the same therapy in the nursery.”

So Weisheit started a 21-day lactation feed regimen with tilmicosin in one of his 1,250-sow farrowing barns. Next door, in an identical barn, he made no changes in order to use it as a control group to gauge economic and health responses. In a few weeks, the results, although not scientifically analyzed, started surfacing.

Baker wasn’t too surprised by the positive results. “We’ve used this protocol before to help clean up Actinobacilus pleuropneumoniae, so we knew it could likely achieve similar results for the coughing baby pigs.” He explains that the young pigs respond so well because there is a reduced pathogen load impacting their respiratory health. “It controls the pathogens affecting the baby pigs and, therefore, improves the overall herd health and performance.”

In the treated barn, Weisheit says pigs were averaging a half pound more at weaning, weighing 14.5 pounds at 20 days, than their nontreated counterparts. Preweaning mortality also dropped from 8 percent to 6 percent.  “We saw a visible difference in the nursing piglets,” Weisheit says. “The pigs on the treated sows stopped coughing altogether.”

After eight weeks, Weisheit had all the data he needed to start treating the sows for improved piglet health. “We began using the same protocol in the other farrowing barn and are seeing the same good results. Now, I even have other producers interested in trying this approach.”

Although Weisheit has long maintained a comprehensive health program for the breeding herd, he now recognizes there’s untapped potential to improve the health and performance of market-bound pigs. “The treated pigs seemed to be more uniform and of a better quality than the untreated ones. I think it’s because they didn’t have to fight disease.”

Baker says this on-farm trial reaffirms his opinion that the industry needs to look deeper into this area. “Reducing vertical disease transmission via the sow is critical if we want to raise healthy, strongperforming pigs through grow/finish. Hank Harris (DVM) helped us improve weaned-pig health through medicated early weaning.  Today, we wean an older pig, and we can impact piglet respiratory health by treating challenges to the sow.”

Science supports method

Swine-health researchers and producers have long known that sows vertically transmit disease to their litters. Less is understood about how sows can similarly transfer “health” to their offspring.

In his ongoing research at Iowa State University, Rodney “Butch” Baker, DVM, continues to look at ways producers can maximize pig health through the sow. “We know sows provide maternal antibodies via the colostrum in their milk; however, there are often differences in this ability between gilts and sows and other subpopulations. So, it leaves the door open for some opportunistic pathogens to colonize in piglets during lactation.”

Butch Baker says at this time, pigs can’t mount a proper immune response and they can fall victim to viral and bacterial pathogens. “These often lead to chronic, subclinical diseases prior to weaning, which may result in slow growth, poor feed efficiency and the pig’s failure to meet its genetic growth potential.”

At MichiganStateUniversity, Barb Straw, Extension swine veterinarian, says producers need to remember that the sow’s ability to pass protective immunity to her litters is quite variable. “Gilts will not provide as much immunity to their offspring because they haven’t been exposed to as many disease agents as sows. But even sows can have large differences in the amount of antibodies they have available to transfer through their milk.”

It’s recognizing that range of available protection and how long it can last that helps producers and veterinarians formulate an effective health-management plan, Straw notes. This will likely involve some new protocols, such as parity segregation, and unique vaccine and antibiotic interventions because she says some old paradigms are being abandoned. “Purposely exposing sows to a large dose of infectious agents is generally not done anymore. This only seemed to stimulate immunity to match the disease organism levels that pigs were exposed to, while it left any missed animals more vulnerable.”

Although superior pig health is paramount, sows also can jumpstart a young pig’s growth even during lactation. “Several studies show that a 1-pound difference at weaning can have positive impacts for the rest of the pig’s life,” Straw says.

Butch Baker agrees. “Our observations show heavy weaning weights yield heavier market weights or less time to reach that weight. However, lactation performance is essential to achieve heavy weaning weights and is the next step after maximizing colostral immunity.”  Certainly, heavier pigs reduce diet costs, improve performance and cut management headaches associated with weaned pigs.

For Butch Baker it all starts with a solid gilt-development program. “It always gets back to husbandry and herd-health management, which is mostly accomplished during gilt development and the breeding/gestation period.”

Back in Indiana, John Baker concurs. “We’ve always emphasized gilt and sow health because we understood what it meant to the herd’s health and productivity. Now, we’re exploring that further by seeing how we can get healthier, more robust pigs at weaning rather than waiting until the nursery stage. It’s the same goal, just achieving it earlier and benefiting from improved gain in younger pigs.”

Even high-health herds should examine the sow/litter health connection. “We still battle respiratory disease in those farms, so it’s important to maintain healthier lungs in young pigs to allow them to perform at a high level through grow/finish.”

In the end, it’s about discovering new protocols that offer long-term dividends. “We understand the advantages of all-in/all-out and reducing horizontal-disease transmission, but we need to look at vertical-disease transmission from the sow,” John Baker says. “We’re on the right track because more producers are interested and beginning to understand the critical role that sows play in getting pigs off to a fast and healthy start.”

Study shows health and performance link

Producers and veterinarians know the importance of maintaining a healthy sow herd to produce healthy and robust pigs. An example of an on-farm study illustrating this point was overseen by Glen Almond, DVM, North CarolinaStateUniversity.

Designed to evaluate the impact of sow health on weaned piglets, the replicated trial showed that lactating sows receiving an in-feed respiratory control product with tilmicosin to address Pasteurella multocida resulted in more pigs weaned, lower nursery mortality and improved respiratory health compared to pigs from control sows. It also produced more pounds per sow (heavier pigs) at the end of the nursery stage.