A study by researchers at Iowa State University found that placing pregnant sows in group housing structures (hoop barns) could be more cost-effective and just as productive as placing them in sow stalls.
The study, conducted for 2.5 years at a research farm in South West Iowa, compared sows housed in stalls to those housed in naturally ventilated hoop barns with straw bedding.
After tracking 957 litters from 353 sows, the scientists discovered that sows in the hoop barns gave birth to more live pigs per litter than those in gestation stalls.
通過對353頭母豬957窩豬的跟蹤，研究者發現，大群飼養的母豬窩產活仔數更多。
They also found that group housing may produce hogs at a cost of as much as 11% less per weaned animal than the sow stalls.
他們同時發現，大群飼養母豬，在斷奶時可節約11%的費用。
Hypothesis The scientists suggested that the bedding and the sows' ability to huddle in the hoop barns, thus controlling their temperature, could have added to their performance.