Retrofitted stalls may compromise sow well-being

Retrofitted stalls may compromise sow well-being

*Krissa Welshans holds a bachelor's degree in animal science from Michigan State University and a master's degree in public policy from New England College. Welshans has long been involved in agriculture and has worked with numerous agricultural groups, including the Animal Agriculture Alliance.

MANY states have imposed bans on individual stalls for pregnant sows. As a result, pig producers in those states have had to develop alternative methods for housing pregnant sows.

One option has been for producers to retrofit the gestation stalls as pens. A study, published in the December issue of the Journal of Animal Science, has begun to shed light on the well-being of sows housed in these pens.

The goal for the study, conducted by the West Central Research & Outreach Center of the University of Minnesota in Morris, was to evaluate the performance of sows housed in retrofitted pens without reducing the sow inventory from what it was when gestation stalls were used. The study was conducted on a 5,000-sow commercial breeding-to-weaning farm in North Dakota.

Large and small pens for group housing pregnant sows were retrofitted from individual gestation stalls. Each large pen was 5.5 x 7.3 m in size and housed 26 sows, and each small pen was 5.5 x 1.7 m and housed six sows. Floor space allowance was approximately 1.5 sq. m per sow in the large and small pens. A total of 338 sows were assigned to large pens, 156 sows to small pens and 325 sows to individual stalls (2.1 x 0.55 m; approximately 1.2 sq. m per sow) that served as controls.

The results of the study showed that sows housed in pens weighed less at day 109 of gestation than sows housed in stalls. In addition, during the 74-day period of gestation that was studied, sows in large pens gained less weight than sows housed in small pens or stalls. However, sows housed in large pens lost less weight during lactation than sows housed in gestation stalls.

Throughout the study, sows were removed from the housing treatments for reasons such as abortion, poor milk production, low body condition, locomotion problems, injuries from fighting, death or euthanasia, prolapse, prematurely weaning the litter, savaging piglets and sickness that was not responsive to treatment.

The sow removal rate was least for individual stalls, at 9.2%, while the removal rate was 15.5% for large pens and 11.7% for small pens. Sows housed in large pens recorded the greatest number of removals for injuries due to fighting (10 of 53 removals) and for poor reproduction (13 of 53 removals).

The results of the study suggest that it will be difficult to maintain performance of the same inventory of sows within a barn of a fixed size if gestation stalls are converted to pens. Additionally, greater space requirements are necessary to group house sows in pens. As a result, fewer sows can be raised during a period.

The researchers noted that sows in this study were first raised in a gestation stall system, and farm workers were not experienced with group housing, which possibly affected the results.


Feral hogs

Feral hogs continue to be a problem for many states across the U.S., and while some states like Oklahoma are discovering a rapidly growing population, other states like Louisiana are home to thriving niche businesses that have capitalized on helping eradicate the pests.

To better understand the feral hog population numbers and impact in Oklahoma, the Noble Foundation launched a survey in 2007 that was conducted by Oklahoma State University Cooperative Extension, the Oklahoma Department of Wildlife Conservation, the Natural Resources Conservation Service and the Oklahoma Department of Agriculture Wildlife Services.

Although the hogs are secretive, making population estimates difficult, the survey estimated the population at approximately 500,000 animals or fewer, with a presence in all 77 Oklahoma counties.

Rooting is the most evident footprint left by feral hogs, but they can also be identified by tracks that are similar to deer but more rounded. In softer soils, the rooted areas can be up to 3 ft. deep, leaving large wallows.

The hogs root around a lot looking for food, usually in broad areas, creating massive soil disturbances, loss of plant material and erosion problems. The hogs then rub on trees, removing bark and leaving mud plastered to tree trunks a few feet off the ground.

Counties in the southeast portion of the state have bigger population numbers, but feral hogs have been forging a path of destruction throughout Oklahoma.

"They are very difficult to control," said Dwayne Elmore, Oklahoma State University Extension wildlife specialist. "Exclusion is almost never practical, leaving lethal control as the best option."

Hog hunters enjoy the sport, while farmers cringe at the thought of their crops being ravaged by the intruders.

Picking off a hog or two at a time through hunting may seem like progress, but many times, the hogs just stop moving during the day and do their damage at night. Elmore said trapping entire groups at a time is much more effective.

"To catch an entire group, consisting anywhere from five to 20 animals, we want to construct a large, round trap," Elmore said. "If there are corners, large pigs will pile up, and some will escape."

An effective way to construct a trap like this is to place cattle panels in a circular fashion, with T-posts tightly securing them to the ground.

"(The hogs) will root under the panels, so make sure they are strongly secured," he said. "You want to pre-bait the trap so the hogs get used to coming in before setting it."

An extermination company in Louisiana, launched in 2011 by a couple of engineers, has capitalized on the U.S. problem by running a thriving business killing the hogs using a radio-controlled airplane equipped with a thermal-imaging camera. Louisiana Hog Control is owned and operated by Cy Brown, the spotter and hunter on the ground, and his partner, James Palmer. In the last six months alone, they have killed hundreds of feral hogs.

Brown uses an unmanned aircraft system that operates about 400 ft. off the ground. He got the idea to strap a high-end camera to a radio-controlled airplane from his hobby of flying miniature aircraft.

Brown recently told Fox News that anyone can build a similar system for about $2,000. That price does not include the thermal-imaging camera, which can cost around $10,000 or more.

Due to Federal Aviation Administration regulations, Brown cannot legally charge people for flying the plane to kill pigs, but he does accept tips, typically about $25 per hog. Larger tips move people higher on the priority list, and while the future of the business is unclear, job security is not expected to be a concern in the near future for the two partners of Louisiana Hog Control.


SowBridge registration

Registration is now open for SowBridge. The sixth year of this distance education program starts Feb. 5, 2014.

University of Minnesota Extension swine educator Sarah Schieck encourages participants to register by Jan. 15 to ensure that they receive the materials in time for the first session.

"The SowBridge program is for people involved in managing or caring for boars, sows and/or their litters, including allied industry personnel, (and provides) access to timely, relevant and accurate information regarding some of the major challenges facing the industry today," Schieck said. "Participants in the past have found the program to be very convenient, affordable and worthwhile."

Twelve sessions take place monthly throughout the year. All sessions start at 11:30 a.m. Central time and last for 45 minutes, which includes time for questions.

The yearlong program is offered by subscription only. The cost is $250 for the first registration from an entity and $125 for each subsequent subscription from the same entity. Registration provides access to one phone line per monthly session and all program materials for each session.

Prior to each monthly session, participants receive a CD containing the session's presentation, along with information to call a toll-free conference line to listen to and interact with presenters.

A brochure containing program topics and registration information is available on the swine extension website at For a sampling of previous SowBridge programs, visit

Volume:85 Issue:52

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