There is a quiet revolution taking place in today's pork industry. Litter sizes are climbing with each uptick in the number of total born and born alive, providing tremendous potential to change farm throughput, according to Minnesota swine veterinarian Tim Loula.

“What we once thought was a big litter will become the herd average,” as operations reach 30 pigs/sow/year (p/s/y) — and turn a dream into a reality, he reported at the 18th Annual Carthage Veterinary Service Swine Conference last fall in Macomb, IL.

Loula, senior partner of the Swine Vet Center at St. Peter, MN, says when producers hear about the trend to 30 p/s/y, they raise two questions:

• What if I'm losing $20-30/pig?

• What if I get a lot of small pigs that I have to sell light?

His answer comes with a review of pig history. Thirty years ago, the late Al Leman, DVM, returned from England saying the United States needed to get to 20 p/s/y to compete with the Europeans, Loula recalls. At the time, U.S. herds were at 14 p/s/y.

By the 1990s, almost all breeding herds were achieving 20 p/s/y. Today, many systems are hitting 25 p/s/y, and some are on the threshold of 30 p/s/y, reaching that level for weeks, and individual sows are achieving 40 p/s/y, he observes.

Sure, weaned pig, sow feed and liquid propane fuel costs have risen significantly. “But weaning more pigs/sow significantly decreases these costs/pig weaned,” Loula says.

For example, when sow feed costs $0.13/lb., 1 ton of feed/sow/year = $260/sow/year. Based on those prices, he calculates increased sow production lowers pig costs as follows:

22 p/s/y = $11.82/pig;

25 p/s/y = $10.40/pig; and

30 p/s/y = $8.67/pig.

Big Drivers

Two years ago, sow feed costs were half of that, reducing the cost/pig proportionately, he adds.

Higher p/s/y obviously drives costs lower on many other related inputs including buildings, insurance, taxes, labor, sow replacements, sow medication, vaccine and semen.

Loula has compiled a list of “big drivers” that will enhance efforts to raise p/s/y.

First is total born/born alive. “The industry is making tremendous improvement in total born and born alive. This will be the key driver in more farms achieving 30 pigs/sow/year,” he emphasizes. “Fourteen total born is happening regularly. The carrot has moved. The old goal used to be 11 born alive; now it is 13.”

He adds: “We've seen the greatest increase in the last several years since the European white line hybrids replaced the U.S. genetic base of three-way cross (Duroc x Hampshire x Yorkshire) breeding programs in the late '70s and '80s.” The European white breeds essentially took over and replaced most U.S. female genetics, he says.

Loula insists that producers will need to achieve 12-13 pigs born alive to stay competitive, and he envisions 13-15 being achievable in the not-too-distant future with genetics leading the way.

Again, the Europeans led efforts to increase litter size, dating back 15 years, and it is really paying off. The top French farms are averaging 28.1 p/s/y, with 14.1 total born, 13.1 born alive and 11.4 weaned/litter.

Increased U.S. reproductive efficiency will result in 90%-plus farrowing rates, increased total born, decreased wean-to-first service interval (5.5 days or less) and decreased non-productive sow days, he predicts.

The pig industry is moving to a later weaning age to improve nursery performance. Loula says there is linear evidence that shows longer lactation length (18-21 days) also plays a role in improved subsequent farrowing rate, total born and born alive. Some systems are actually moving to 21-23 days wean age.

Avoid overbreeding, he cautions, because it can result in early weaning, an increase in litters of less than seven pigs born alive and more fall-out pigs. Early weaning also has other effects on reproductive performance:

• Decreased total born;

• Prolonged wean-to-first service interval;

• Shortened estrous cycle; and

• Lowered farrowing rate.

Don't try to compensate for a short breeding group by early weaning some animals, because those females will breed at the same time they would have if they were allowed to lactate 3-4 more days,” he emphasizes.

To achieve high total born to reach 30 p/s/y, producers must pay closer attention to their gilt development programs.