National Hog Farmer is part of the Informa Markets Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Sows Flourish In Pen Gestation

Records document top reproductive performance and lower sow mortality rates as Goldsboro Hog Farms' 72,000 sows thrive in pens.

Records document top reproductive performance and lower sow mortality rates as Goldsboro Hog Farms' 72,000 sows thrive in pens.

In 1989, the Maxwell Family, owner/operators of Goldsboro Milling Company, which is ranked as one of the nation's top 10 turkey producers and processors, was faced with excess milling capacity. Recognizing the success of their neighbors in the pig business, they decided to diversify.

A call went out to Bob Ivey, veteran pork producer/seedstock supplier, to draft a blueprint for the company's entry into the growing North Carolina swine industry. Jim Maxwell was the family member most interested in the new venture and worked closely with Ivey.

Ivey, with his brother, Ted, had established Ivey Spring Creek Farms as a successful seedstock supplier and production management consulting firm.

Bob Ivey signed on as general manager of the new Goldsboro Hog Farms, headquartered in Goldsboro, NC. “We not only provided production management protocols, but also designed the facilities, provided cash flow projections and business management,” Ivey explains. “Fortunately, they are a very progressive company. They allowed me to be very creative in my approach to swine production and were willing to give me all the tools and support needed to be successful.”

Goldsboro Hog Farms built their first 1,000-sow farm in 1989. The Maxwells found they liked the hog business. Fueled by ample packing capacity in eastern North Carolina, they spent the next six years in rapid expansion, adding sows in increments of 2,000. By 1995, they had grown to about 66,000 sows.

Goldsboro Hog Farms currently ranks amongst the top 10 pork production systems in the U.S. with about 72,000 sows — all housed in pens during gestation.

Using the description “progressive company” and “pen gestation” in the same breath may seem a contradiction of terms to some — but not to Ivey.

He acknowledges that many systems use gestation stalls very successfully. While he doesn't see crated gestation as a huge animal welfare issue, he recalls the animal welfare pressures being waged in Europe before he began designing the Goldsboro system. He expects that similar animal welfare concerns will someday have an impact on U.S. production schemes.

In the Goldsboro system, newly weaned sows are moved to a row of individual stalls adjoining a breeding pen. Sows are turned into the breeding pens for estrous detection, then returned to the stalls. Boars are brought to the cycling females for stimulation during artificial insemination. Thirty-five days later, sows are pregnancy checked.

The advantages Ivey sees in the short-term stay in the stalls include:

  • Individual feeding of sows to return them to their prefarrowing body condition;

  • Heat checking and artificial insemination is easier and more efficient; and

  • Stalls help avoid injury from fighting or cycling sows riding each other during their most vulnerable post-lactation period.

“From an animal welfare standpoint, I felt I could defend keeping animals individually housed for 35 days, if it ever became an issue,” Ivey says.

Sows confirmed pregnant are sorted by size and parity and placed five per 8×10 ft., partially slotted pen. This provides 16 sq. ft. of space for each sow — just 2 sq. ft. more than a typical 2×7 ft. gestation stall. “But they have access to all of the space in the pen,” he adds.

“With five sows/pen, you are more able to get them sized up with the same type of animal,” Ivey explains. “That's more difficult with larger groups. I think most of the dissatisfaction with pen gestation comes when you try to put too many sows into the pen.

“People don't want to go back to pen gestation because they seem to think it's a sacrifice that they can't manage,” he says. “It's obvious by Goldsboro Hog Farms' production levels that it can be managed without too much concern.”

Proof in the Performance

When producers become skeptical whether pen gestation will optimize reproductive performance, Ivey points to Goldsboro's top ranking in the AgriMetrics system, then cites the more widely used PigChamp recordkeeping system to reinforce reproductive performance (2003 PigChamp summary data representing 252 farms and approximately 225,000 sows appears in parenthesis below for comparison of key production measures).

Data from 51 Goldsboro farms in full production during a 12-month period ending Sept. 30, 2003 recorded an 84.1% farrowing rate (81.96%), 10.1 pigs born alive/litter (10.57) and 2.48 litters/mated female/year. Pigs weaned/mated female/year tallied in at 22.7 (19.56) with an average litter weight of 141 lb. (79.09), at an average weaning age of 19.2 days (17.81).

Concerns about injury and death loss in pen gestation are laid to rest when he points to the 5.7% (9.1%) mortality rate. Culling rates are a self-imposed 52%. “We don't have the genetic costs in our animals (see sidebar), so we set it at 50%,” he explains. “We could easily set it at 45% or whatever.”

Average parity for the period was 3.2. Non-productive sow days (NPD) came in at admirable 35.1 days. “When NPDs come in under 40, you can't have many recycles. We really focus on that,” he says.

The Benefits of Pens

Ivey ticks off several reasons Goldsboro sows often outperform more popular stall gestation housing, and he offers management tips to make pens work:

Better water intake — High on his list of benefits is the near elimination of urinary tract infections. Ivey believes when sows move around more, they drink more water and, consequently, they urinate more. All are pluses associated with urinary tract health. Better health translates to less sow mortality.

“I don't agree with using water troughs because they restrict water intake,” he adds. Nipple waterers are now being replaced with bowl waterers to minimize water wastage — a growing concern as lagoon levels are increasingly scrutinized.

Better floors — With less concrete floor erosion where sows eat and drink, “the water and feed aren't right there eroding the concrete, exposing the pebbles and sharp rocks that can cause feet and leg problems and shoulder sores,” he says.

Ivey also believes sanitation is better in pens than stalls because sows work manure through slotted floors better.

Less maintenance — “Based on my experience, after 10 years, individual crates wear out. Broken crates can cause injuries,” he concedes.

Sow condition — Typically, feeding levels are adjusted only twice. At weaning, sows are placed on full feed until bred and fed individually in stalls for 35 days to regain proper body condition. After passing the 35-day pregnancy check, sows are moved to pen gestation. Feed is cut back until their last 30 days of gestation, when feeding levels are increased based on parity and condition. “Because of the competition in the pens, the last 30 days seem to be the best time to adjust feeding levels,” Ivey explains.

Mixing and fighting — The sows' 35-day stay in the stalls allows them time to recover from farrowing, nursing and weaning stresses. Once confirmed pregnant, groups of five sows or six gilts are matched up by size and parity. “You need to use some common sense,” Ivey explains. “You don't put a 500-lb. sow with a 300-lb., first-parity gilt. There is some fighting, but not very much. It's not a problem.”

Sow health — “Another advantage is sows have nose-to-tail contact, so in these large sow herds you can stabilize (disease) subpopulations a whole lot quicker because the animals are better exposed to each other,” he says. Vaccination and medication is easier in pens if done when sows are eating. “You don't have to reach through the (crate) bars to treat them,” he adds.

Catching recycles — Occasionally, an open sow will slip through or abort her litter after the 35-day pregnancy check. “Another advantage for pen gestation,” says Ivey. “It is easy to recognize recycling sows in pens when they ride other sows.”

Whether recycling sows are bred again depends on their history. If she has recycled before or she is older, she may be culled. Those that are rebred are sent back through the breeding area stalls, pregnancy checking and regrouping procedure.

Converts — “We've bought a few farms that had gestation stalls, but we've converted them all over (to pens),” Ivey explains. In one case, during the early expansion years, another genetic line was being used in about half of the Goldsboro units. The company was convinced their animals performed better in gestation stalls. But when it came time to double the sow herd, they built another 1,000-sow barn with gestation pens. With the same genetic lines and the same manager overseeing both barns, “the side with the pen gestation outperformed the other,” he says. “The unit has now been converted to all pens.”

Ivey has had similar reactions when managers from crated gestation units are hired to run a Goldsboro facility. “Most everyone likes our system better. They realize it's easier to move sows, the animals appear more comfortable and it's easier to find recycles,” he says.

Hand feeding — “The only thing employees don't like about our system is that we make them hand feed the sows; that's a pet peeve of mine and it's not negotiable,” he explains. “I believe in hand feeding because I believe in the people-to-pig contact. When you hand feed, if all five sows don't come to eat, you know you have a problem in that pen.” The hand feeding also reinforces a positive association between people and the sows, which reduces stress when sows are moved. Records indicate gestation feeding averages 4.43 lb./sow/day.

Closing Thoughts

“Philosophically, I don't like individual crates all the way through (gestation and farrowing). That's why our system is designed with pen gestation. I'm not saying an animal is less happy because it's in an individual crate.

“All I can say is, the animals seem to be more comfortable in pen gestation and that's reflected, I think, in their performance, with the added benefits of reduced maintenance costs,” Ivey explains.

Carts Ease Stress at Weaning

Custom-made weaning carts have made weaning day less stressful on pigs and people at Goldsboro Hog Farms. General Manager Bob Ivey got the idea from the caged-turkey transport trucks. The four-tiered carts on large caster wheels have eight compartments, and hold about 50 pigs (depending on size).

Compartments open at both ends of the cages, making it easy to load them directly from the farrowing crates. Pigs are sized and sexed at weaning, making it easy to stock nursery pens and minimize sorting later.

On weaning day, the transport truck arrives at a predetermined time. Empty crates are rolled off to make room for the loaded carts. Empty carts are used for the next week's weaning.

“We have a set of scales at every farm where each cart is weighed before it is rolled on to the environmentally controlled truck,” Ivey explains. “This not only gives us the total weight, but we can see the weight distribution. This helps us keep up with the number of pigs that weigh less than 8 or 10 lb.

“A lot of people focus on pigs out the door, but they do it at the expense of quality or pig weight. By weighing the pigs, we can focus on pounds of pork weaned, as well as numbers weaned per sow,” he continues.

Weaning age ranges from 14 to 22 days; pig weights generally average about 13 lb. Ivey prefers the slightly heavier weights at weaning because it usually means the pigs are a little older. “Then, we don't have to spend the extra money putting a couple of pounds on a pig with a more complex, expensive diet,” he says. “There's an age factor, but there is also a size component to that. If you have a heavier pig, you can fudge on those diets a little bit more. For every pound heavier a pig is at weaning, he will come out of the nursery 3-4 lb. heavier.”

One 50-pig cart fills two nursery pens. “Usually, we only have to handle each pig twice — once to put him in the cart, and once to take him out and place him in the nursery pen. It's efficient and very low stress on the pigs,” he says, adding: “It makes the pigs happy and it makes the people happy because they aren't bending over to sort pigs again.”

Unique Genetic Combinations

Goldsboro Hog Farms has partnered with Ivey Spring Creek Farm (ISCF) in a genetic program unique to the swine industry. The ISCF program incorporates two breeds — Chester Whites and Durocs — recognized for their meat quality attributes in the National Pork Board-funded genetic evaluation programs.

On the female side, the ISCF Chester White maternal dam has excellent pork quality and sow productivity traits. “This female is a key component for the quality in the ISCF Chester-Landrace-Large White cross females used extensively in the Goldsboro Hog Farm system,” explains Bob Ivey. “They are bred to the ISCF Duroc terminal sire to produce pork with excellent color and firmness that is juicy and tender. We call this our ‘Golden Delicious’ pork.” The Duroc, Landrace and Large White lines originated in Denmark and were bred and adapted for the heavier market weights in the U.S.

“The majority of the Goldsboro system is the Chester White bred to Landrace to produce the grandparents; then they are bred to Large Whites to produce the parent sows, which are bred to Duroc boars,” he explains.

“The beauty of our program, by having three different white breeds, is I don't have to farrow a lot of purebred animals,” he continues. “Heterosis is a freebie. More genetic progress is made through heterosis than anything — especially for maternal (reproductive) traits. By taking advantage of heterosis, we can take a few Chester White females and breed them to Landrace, then breed those F1s (first-cross) females to Large Whites to produce the parent females needed. Basically, we've captured 100% heterosis at every step except the great-grandparent (ggp) level. We have very few animals at the ggp level.

“So, in other words, 1,000 Chester White ggps at a 50% selection rate can produce 5,000 grandparents. Those 5,000 can produce 25,000 parent animals. It's very efficient multiplication and the lines are distinctively different.”

ISCF was founded in 1976. Bob and Ted Ivey, the principal owners, currently supply genetics to companies producing over 2.8 million market hogs annually.