Large groups of pigs to be finished can be housed in one pen, provided that auto-sort technology is included to enhance feeding and marketing strategies.

A few years ago, the Pig Production Division of Belstra Milling Company, Inc., dabbled with housing 100-125 pigs/pen in grow-finish barns. “We really liked the way the animals related to people and to each other, because there was no social hierarchy,” says Malcolm De Kryger, vice president at the DeMotte, IN,-based company.

But sorting and marketing out of those large-pen barns was a real struggle.

“We really didn't have the technology to sort them. You'd try to sort the 20 largest pigs out of 400 in a barn, and even with 10 guys, you could hardly do it,” recalls Rob Buiter, head of contract finishing. He says the “roundup” would start a week in advance to gradually move groups of pigs out of a barn.

All that changed in late 2002 and early 2003, when Belstra worked with area producers to remodel or build about 20, 600-900-head, auto-sort finishing barns, says De Kryger. Some house hundreds of pigs in one big room in a barn. Others, like Iroquois Valley Swine Breeders (pictured), house 800 head divided into two groups.

What drives auto-sort systems is the scale. The scale can be set to divert pigs to the sort pen at the proper weights for marketing, based on packer buying patterns, says Jon Hoek, Production Strategy coordinator for Belstra.

“In an 800-head barn, you are going to have 30-lb. weight variation in a group, and that's where the auto-sort system comes in. It's like picking fruit. We want to pick the ripe ones first — take the top 10-15% at 270 lb.-plus — and leave the rest to grow for another week,” he notes.

Auto-sort systems being used are from Schick Enterprises (Figure 1), Staco-Choretime and Raytec, and one operation has both Raytec and Farmweld auto-sort systems. The systems are being used in both single- and multi-site operations, with pigs placed on feed at about 60 lb. Barns are filled in two-week intervals.

Today, the Belstra system finishes 150,000 pigs/year with roughly 45,000 pigs produced/year in the big-pen, auto-sort barns.

Belstra Background

Belstra Milling is a family-owned enterprise that just celebrated its 50th anniversary in business. The Belstra Group consists of the feedmill at DeMotte, five PIC gilt multipliers comprised of 7,000 sows in northwest Indiana and northeast Illinois, and a 160-head boar stud.

Genetics are the core business of the Pig Production Division, led by sales of semen and replacement gilts, points out Hoek. Barrows are fed out at multiplier farms, with excess barrow production contracted to area feeder pig finishers.

At the five multiplier farms, gilts are fed out and selected as replacements at 250 lb., while barrows are finished to 260-270 lb.

All of the different large-pen, auto-sort barns associated with Belstra feature totally slotted floors and are tunnel-ventilated. Barrows and gilts at gilt multipliers are penned separately. Wet-dry feeders are commonly used. Pen density is 8 sq. ft./pig.

Those building features are fairly standard. But the “free range,” large- pen design holds many attractions for the people working in the facilities and also for the pigs, says De Kryger.

“The personality of these pigs in big pens is good. They get along with people and with each other, partly because there is daily, direct interaction with people. There is no fright and no flight (response),” he observes.

Most Belstra auto-sort barns don't have aisles or alleyways (Figure 1). In a typical 40 × 216-ft.-long finishing barn, the space savings from not having a 3-ft. alley translates into an additional 648 sq. ft. (216 multiplied by 3), enough for 75-80 more finishing pigs based on 8 sq. ft./pig, says De Kryger.

Pigs appear very comfortable with producers hopping gates and walking in the pens to observe pigs, he notes. Producers are advised to walk pens two to three times a day.

Astute Management Required

De Kryger, and Belstra swine consulting veterinarian Tom Gillespie of Rensselaer, IN, agree that producers need to be astute managers to closely survey the health of such large groups of hogs. Producers should watch for pigs that are falling behind and especially look for gaunt pigs, says Gillespie. These may be timid pigs that are afraid to enter the scale. Auto-sort systems require pigs to cross the scale in order to access the food court.

Hoek points out that 75% of the building area is set up for sort pens (for load out), and as the general population or loafing areas where pigs run, play and sleep. Pigs usually sleep back-to-back from the edges of the room toward the center, providing the appearance of extra pen space.

That leaves 25% for the food court. It may appear cramped, but the goal is to provide enough space for the pigs to eat and leave, and not enough for them to loiter, says Hoek. “If pigs try to take a nap in the food court, they will probably get walked on,” he says.

Provide an 8 × 8 sq. ft. or 10 × 10 sq. ft. area in a corner as a hospital pen, suggests Hoek. Unlike traditional finisher barns, hospital pens are temporary structures in large-pen finishers. Once pigs feel better, they can be released back into the general population without being picked on, adds Hoek.

As a rule, pigs in the general population are relaxed and seldom fight except when barns are filled, adds Buiter.

Gillespie remembers the first time he experienced that relaxed atmosphere during an outbreak of swine flu in a 660-head pen in an auto-sort barn.

“I was able to easily walk through that unit. It was amazing. Except for a group of 12-15 pigs that followed me, other pigs did not even get up when I took their temperature! Granted, they had low-grade fevers and were not feeling the best, but I was able to walk right up to most of them and (quickly) give them shots without having to even corner most of them with a board.”

In the event of a respiratory disease outbreak in a large-pen barn, if wet-dry feeders are used, sick pigs may not have the energy to walk through the scale to get to the food court, he warns. Therefore, it may be wise to install some hanging nipple waterers in the general population areas.

Other Auto-Sort Advantages

Auto-sort systems offer real savings for marketing efforts, says De Kryger. Groups of 200 to 250 pigs move easily into sort pens that are set up 24-48 hours prior to shipping.

De Kryger dispels the notion there is a pecking order established in sorting pens. “There are no pecking orders in these auto-sort barns, so if you take 65 out, there is no new pecking order,” he stresses. “That makes it really possible to pull off a few head from each finisher barn to get the most uniform pigs possible.”

Belstra data shows sort loss is cut in half in auto-sort barns vs. conventional finishers.

Marketing labor is also greatly reduced, notes Buiter. Hogs have been “trained” to move in groups. They load and unload easier. Because the pigs have already been sorted using the scale, pigs can be removed to hit target markets as needed.

At times, Buiter has loaded trucks with 200 head of hogs in an hour by himself. At $15/hour, De Kryger points out that two men can load a semi with 200 hogs in a half-hour at a cost of just $15. In contrast, De Kryger estimates it takes three men one hour to load the same truck from a conventional barn — or triple the cost of the auto-sort barn.

De Kryger also estimates it costs half as much in pressure-washing labor to clean an auto-sort barn as it does a conventional finishing barn, due to less gating and pens.

In all, the savings in sort loss, sort labor, wash labor and feed amounts to several thousand dollars in savings/room/year for the big-pen, auto-sort barn, he adds.

Costs are higher for new auto-sort construction, however. De Kryger suggests a 1,000-head finishing barn with conventional gating will cost $7,000-$8,000 vs. $8,300 to $11,400 for a 1,000-head, big-pen finisher with auto-sort.

Belstra staff agree that the addition of big-pen with auto-sorting has allowed better control of the whole production process.

And while there are differences in the auto-sort systems Belstra uses, all have features that make them valuable, and any problem areas can be handled through management, says De Kryger.

Comparing Finishing Barn Performance

Performance data comparing one auto-sort barn and one conventional finisher in the Belstra system hasn't shown a clear advantage to the auto-sort barn, points out Jon Hoek, Production Strategy coordinator for Belstra Milling.

Table 1 reflects nearly identical results for average daily gain, feed efficiency and average daily feed intake, but about 4% less feed cost per pound of gain in favor of the auto-sort system, he says.

Numbers of fatigued market pigs, “off” butchers (lights, belly busts, etc.) and mortality rates are slightly higher from auto-sort barns, although Hoek stresses these results are not statistically significant when comparing auto-sort or conventional finishing operations.

Table 1: Results from Auto-Sort vs. Conventional Finishinga
Max-L Farms Big Pen Finishing w/ Auto-Sort 1,800-Sow Farm Hopkins Ridge Farms Conventional-Pen Finishing 1,200-Sow Farm
Barrows & gilts sold 20,089 16,668
Average sale weight 244 lb. 246 lb.
Average daily gain, 60 lb. to market 1.81 lb./day 1.9 lb./day
Feed efficiency 2.77 2.75
Average daily feed intake 4.99 lb. 5.2 lb.
Feed Cost/lb. of gain (U.S.) 0.2191 0.2226
Fatigued market pigs 0.38% 0.33%
Off butchersb 3.09% 3.19%
Mortality 1.85% 1.64%
a1st two quarters of 2004
bThese market hogs are sold as lights, belly busts, etc.