Research has shown that sows housed individually within farrowing crates have a lower stress hormone than those housed within groups. The farrowing stalls protect sows and their piglets from other aggressive sows. Aggressive sows will attack other sows and their piglets resulting in injury and or death.
Pigs are pack animals, and present some of the same behaviors as wolves do. Pack animals generally establish a hierarchy within their pack known as a boss sow. This hierarchy is achieved by fighting and attacking one another. Fighting like this can result in broken backs, legs, and torn or bitten ears and tails. The boss sow not only attacks other sows, but may also bully them for food. Many of these attacks result in pregnancy termination.
The reason for the decrease in stress hormones of sows that have been housed individually was because they no longer had to fear the boss sow, or other aggressive sows. Wanda Patsche shared this story of her personal experience with aggressive sows on her hog farm. “One particular incident I remember like it was yesterday was a perfect example of why we considered a change in how we housed our animals. Shortly after a thunderstorm a sow gave birth to piglets outside. She didn’t make it to the farrowing barn. Even with the best planning, sometimes births happened outdoors. Unbeknownst to us, another sow picked up each of those baby piglets, took them outside and drowned each one of them in a mud puddle.” As you can see, sows can be savages. This is why many pigs prefer having farrowing crates as protection from sows such as this.
Reference List
Schultz, S. (2014, April 15). Why Do Hog Farmers Use Farrowing Crates? . Retrieved from http://www.nurselovesfarmer.com/2014/04/farrowing-crates/
Patsche, W. (2015, February 9). WHY WE USE INDIVIDUAL GESTATION STALLS FOR OUR SOWS. Retrieved from http://www.mnfarmliving.com/2015/02/why-use-individual-gestation-pens.html
Heinsohn, B. (n.d.). Use of Gestation and Farrowing Crates in the United States. Retrieved from http://www.cookcfb.org/articles/entryid/450/use-of-gestation-and-farrowing-crates-in-the-united-states
AEE 311: Farrowing Crates 