Hog hoop houses look to be a good buy. The lower building costs of hoops at $55/pig capacity vs. double-curtain finishers at $160-180/pig capacity are basically offset by reduced performance and increased backfat in hogs raised in hoops.
Analysts say the real determining factor for successfully raising pigs in hoops is how producers manage bedding.
Mike Brumm, University of Nebraska swine specialist at the Northeast Research and Extension Center, Concord, NE, says the secret of construction savings is the bedding used to insulate the pigs in cold weather. In one year, the amount of bedding averages 1 lb. of residue per pound of gain. Once pigs are sold off, the bedding is removed and the process starts all over again.
Jay Harmon, extension agricultural engineer at Iowa State University, suggests on average that producers finishing 150 head of hogs in a hoop building should use about 200 lb. of bedding per pig finished. For cornstalk bales (1,000-lb. bales), you would need about one bale for every two-pig capacity. Therefore, you would need about 75 bales of cornstalks in a 150-head capacity hoop, he says.
If you put up 10 hoop structures, you're talking lots of cornstalk bales. Producers should know how to handle them, particularly how to avoid deterioration in the spring before they get used, warns Harmon.
"When it comes to hoops, the idea is to put down enough bedding to capture the urine but not allowing the nitrogen to seep into the ground," says Harmon.
"The overall key to the whole system is bedding," he adds. "If you don't have the bedding and aren't willing to put enough bedding down, pigs are just going to be cold and not perform well."
At first, skeptics said hoop buildings wouldn't be warm enough for pigs in winter, especially in northern climates like Iowa, says Kurt Van Hulzen, DVM, Animal Health Center, Sac City, IA.
Bedding Pack Warms Up But from using a probe 4-6 in. into the bedding in some of the clinic's own hoop structures, he found that temperatures ranged 100-110 "degrees" F and rarely dropped under 90 "degrees" F.
"You are dealing with kind of a micro-environment," Van Hulzen notes. "Don't worry about the air temperature inside the building. It may only be 10 "degrees" F higher than the outside temperature.
"But you're not trying to warm the whole building up. What you're trying to do is manage that bedding pack so that pig has an area to go to that is more his comfort zone," he explains.
On a winter morning, all you will see when you walk into a hoop building are "ears and eyeballs" from those pigs burrowing down into that bedding pack, Van Hulzen says.
"The biggest problem we see with producers is inadequate bedding," he says. "If you are doubtful whether to add a bale or not, err on the side of safety and add another bale."
In Van Hulzen's northwest Iowa practice area, the common bedding for hogs is cornstalks. His rule of thumb is to add around two large bales a week to hoops in winter, then cut back to about one bale every 10 days in summer.
Less Bedding In Summer In summer, producers should manage the bedding pack differently, he says. Let the bedding get a little moister. Don't add as much bedding so it retains a little moisture and it will give off an evaporative cooling effect. If summers are extremely hot, as was the case a few years ago in northwest Iowa, install a sprinkling system to provide a misting effect down over the bedding pack.
There are many different kinds of bedding material which can be used in hoops including straw, cornstalks, soybean stubble, prairie hay, oat wheat straw (popular in Canada) and shredded paper. Any biodegradable material will work as long as it holds in heat, is readily available and is fairly cheap, says Van Hulzen.
For producers working alone in hoops, it's advisable to go to smaller, 4-ft. bales which can be added to the building by one person.
Turkey Litter In his veterinary practice, turkey litter is also very popular because of its availability and no cost to producers. The only charge is a trucking fee to haul it to the hog farm.
Turkey litter is composed of 90% wood shavings (sawdust) and 10% fecal material. At the farm, producers dump it, cover it with a tarp and compost it for two weeks. That way, when it is placed inside the hoop building, it is virtually pathogen-free, explains Van Hulzen.
His veterinary clinic ran some trials and found that during composting, temperatures reach well in excess of 100 "degrees" F for sustained periods of time. That kills the two biggest disease concerns for pigs: erysipelas and tuberculosis.
"The other reason that we like the turkey litter is because if you're starting new pigs in hoops in December and January, by putting that turkey litter in, you've already got heat generation going on so that bedding will already be pretty warm for those new pigs," he points out.
A tractor and loader or skid-steer loader with grapple hook is needed for bedding removal. Van Hulzen estimates it should only take six to eight hours to clean out a hoop building start to finish. This includes field application, power washing feeders and waterers and rebedding.
Manage bedding properly. Keep pigs warm and dry. Manage the end doors to keep out drafts. Provide proper ventilation. Do all that and pigs cando very well in hoop facilities, he says.