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Slideshow: Researchers have found many benefits to the ESF system, though it’s not right for every farm.

Chris Torres, Editor, American Agriculturist

October 28, 2019

6 Slides

It’s feeding time at the University of Pennsylvania’s Swine Teaching and Research Center in Chester County’s horse country.

Actually, it’s always feeding time in this loose pig environment. Sow gestation stalls are gone, free-roaming pig pens are in. The sow decides when she wants to eat, not the other way around.

Each sow is tracked through an RFID tag attached to her ear. When she’s hungry, the sow gently walks into an electronic feeding chute where a select amount of feed is provided. Tom Parsons, professor of swine production medicine and director of the center, uses a computer to keep track of how much each sow has been fed and can adjust it based on how far along she is in her pregnancy.

About 20 years ago, the center showcased its very first prototype of an ESF system. Today, more than 200,000 sows across the country are being raised in similar systems, according to Parsons.

He’s convinced that gestation pens in combination with ESF systems are the way of the future for modern pig production.

Pens and technology

Gestating stalls have long been used by pork producers to prevent pregnant sows from nipping, biting and being aggressive, and are an efficient way of producing piglets for finished production.

“Whenever pigs are together, they form a social hierarchy,” Parsons says. Dominant pigs will emerge and outcompete other pigs for feed and nutrition, leading to discrepancies in nutrition, body condition and injuries.

But with gestation stalls falling out of favor with consumers and the general public, integrators have searched for alternatives that can also preserve production. 

Having spent time in Europe looking at alternative gestation systems, Parsons’ goal was to develop a system that would be optimized for U.S. pork production.

At the center, the pens are 20 feet wide and run the length of the barn on either side. They can be configured to accommodate anywhere from just 60 sows to well over 200.

“It's not an accident that these pens are long and narrow," he says. “What we know is that a dominant [sow] will only chase a timid sow so long until she gives up; that's about 30 feet of a flight zone. If you look at pigs in the wild, they almost never fight because they have no boundaries; they will avoid each other if they don't like each other.”

What about feeding? This is where technology becomes a crucial part of the system.

When a sow needs to feed, all she does is step into an electronic feeding station where the station reads the RFID tag and dispenses a specific amount of feed assigned to her.  

The feed station itself is equipped with two hoppers with two different rations. The center produces organic piglets that are finished and marketed for premium pork, but Parsons says the organic regulations only require gestating sows be fed organic feed during the last trimester.

The center’s record-keeping software is integrated with the feeding system, so each sow is fed on a feed curve based on days of gestation. Right up until day 75 the sow is fed conventional. During the third trimester, she is automatically switched to organic.

"That's one of the feasibility pieces of this, which is such a nice mesh with the technology," he says.

Parsons says research has shown that overfed sows will deposit fat into their udder, reducing lactation. The system can be adjusted to drop feed amounts for 10 days to prevent overfeeding, then increase again at the end of gestation for proper fetal growth.

Sows go through the feeder in essentially the same order every day, something Parsons thinks has to do with social hierarchy.  

“That’s what I like about this system is that it allows pigs to be smart," he says.

The target range is to feed between 70 and 75 sows per ESF station. The number of feeders per pen is proportional to the number of sows in the pen.

“Not only do we feed sows as well as we did in the gestation stall with this technology, we can do it better,” he says.

From lab to farm

Proving a system can work in the lab doesn’t mean anything if it can’t work on a real farm.

In 2007, Parsons and Penn Vet started collaborating with Country View Family Farms, the hog procurement and production wing of Hatfield Quality Meats, on converting one of their sow operations to an ESF facility.

At the same, he says, they worked with Schwartz Farms Inc., a 5,000-head operation in Minnesota, on converting the operation to ESF.

“They see it as part of a competitive advantage,” Parsons says of companies converting to ESF.

In the case of Country View, ESF allows them to market a portion of their animals under their Farm Promise brand, which promotes family farms, no antibiotics ever and group housing. It also fetches a higher price at the store.

Bob Ruth, president of Country View, says the company launched their ESF system after consulting with Parsons and seeing similar systems in Europe.

Ruth says they first developed a test farm where they wanted to see if they could get as good or better production in ESF. Production didn’t increase in the ESF system, but it didn’t get worse either. Ruth says he liked the system because it allowed the animals to move around.

Of the 10 company-owned sow farms, seven have been updated to ESF. Ruth says they’re planning to install ESF systems on all new farms as well as on remodeled operations. They currently contract with 250 local farms to grow out their feeder pigs.

Ruth says they’ve focused on a preimplantation system, meaning that the sow is in an open-pen environment during the entire pregnancy.

Still fighting

The system is far from perfect, Ruth says, especially when it comes to sows not hurting each other.

“We continue to improve it, but if there was one thing we would love to figure out, it is this,” he says.

Ruth says they’ve gone to more sows per pen — from 70 to more than 200 per pen — as the more sows there are, the less they want to fight. They’ve also started applying smell-reduction sprays — a mix of iodine and water — to the sows to reduce the smell factor that often leads them to fighting.

All about people

Even with all the technology, having the right people is crucial to an ESF system working.

“You really are looking for people who are good husbandry people and understand technology, too,” Ruth says. “I wouldn't call it a unique skillset, but a lot of our older term team members, we had to work with them to get them to rely on the information and go out and find the animals vs. the old way where you can easily see the animal and take care of the situation right away."

Animal husbandry skills come in handy, for instance, when trying to look for sick or lame animals. In an ESF system, dominant sows tend to congregate in front of the electronic feeder entrance. The sows then separate into smaller groups according to their social hierarchy, with the less dominant sows ending up toward the bottom of the pack.

Parsons says that he works with producers to look for pigs in the corners of pens as this where many will congregate if they are sick or lame.

He says that too many pork producers get caught up in the ag engineering portion of an ESF — how much space per sow, where the feeder is located — whereas the animal husbandry and people portion is even more important.

“The people you have to get right every day,” he says. "Most of the companies that do this are really good at raising pigs in a stall, but my experience is they haven't taken enough time to think how things are going to be different.”

“I don't think that industry is adapting it as much as we have,” Ruth says. “Change is hard and some people like change, some people don't. We've had to learn and train and organize differently, and it hasn't been an easy task.”

Bigger pens, higher cost

Ruth says they’ve gone to larger group pens with no adverse effects on performance or animal health.

Parsons says the threshold can be anywhere from 60 to 280 sows to a pen. The key, though, is giving each sow enough room to move to prevent aggression and fighting.

Parsons says that they initially recommended between 20 to 22 square feet per sow, but that number has increased from 22 to 24 square feet as producers have become more focused on optimizing management of this type of group housing.

If you do a comparison of equipment, Parsons says you’re essentially trading a lot of steel in a crated system for more technology in an ESF; in the end, it’s essentially a wash. But you need more room in an ESF.

What researchers have found over time, he says, is that in order to accommodate the necessary square footage per animal as well as provide enough flight space in a pen at least 10% more space is needed overall.

“The bigger the pen, the better it is for the pigs,” he says.

On the 80 farms he’s worked with, all of which have almost the same physical footprints — most of the operations have 5,000 sows or more — the results have been mixed. Some operations are doing well, while others are struggling.

This is where looking at an operation in a more holistic way, from farrowing to finishing to marketing, is important when thinking about an ESF system.

"I can raise a welfare-friendly farm, but I can't raise just welfare-friendly pork chops," Parsons says. “That’s a challenge on the marketing side. If you can only sell part of the carcass as premium, is there enough value to pass back to the farmer if you have to sell a big part of the animal at regular commodity prices?”

Not for every farm

Parsons admits that ESF systems are probably not for every pig farmer.

“We're trying to identify the mid-majors of pork producers and integrators, farms that are small enough to really still put value on high-quality employees and are paid well,” he says. “To me, it's not a question of whether pen gestation can work, it's a question of whether or not you can make pen gestation work? Will it work for you?”

“If you have good people, then the large pens are going to be the better solution. If you don't have good people, maybe you need to be feeding on the floor.”

About the Author(s)

Chris Torres

Editor, American Agriculturist

Chris Torres, editor of American Agriculturist, previously worked at Lancaster Farming, where he started in 2006 as a staff writer and later became regional editor. Torres is a seven-time winner of the Keystone Press Awards, handed out by the Pennsylvania Press Association, and he is a Pennsylvania State University graduate.

Torres says he wants American Agriculturist to be farmers' "go-to product, continuing the legacy and high standard (former American Agriculturist editor) John Vogel has set." Torres succeeds Vogel, who retired after 47 years with Farm Progress and its related publications.

"The news business is a challenging job," Torres says. "It makes you think outside your small box, and you have to formulate what the reader wants to see from the overall product. It's rewarding to see a nice product in the end."

Torres' family is based in Lebanon County, Pa. His wife grew up on a small farm in Berks County, Pa., where they raised corn, soybeans, feeder cattle and more. Torres and his wife are parents to three young boys.

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