Reducing the environmental footprint of pig finishing barns

Inexpensive energy (fossil fuel and feed), plentiful water, and limited concern of air emissions has resulted in few incentives to critically evaluate, modify, or significantly change pig housing designs. However, recent global trends have forced the pork industry (both in Midwest and throughout the U.S.) to reduce the environmental impact of swine production systems. This could partially be accomplished through the development and use of smarter and/or "greener" housing designs and management that reduces both fossil and feed energy use as well as air emissions including hazardous (ammonia and hydrogen sulfide) and greenhouse (carbon dioxide, methane, and nitrous oxide) gases plus odor and particulate matter. A new pig finishing housing design is proposed in this paper which is referred to as the "Greener Pig Barn" or GPB. This report includes four GPB design variations. All GPB design versions use shallow gutters with mechanical scrapers and an in-ground, covered, concrete manure storage tank so a reduction in air emissions are expected due to the lack of long term manure storage inside/under the barn and to barn cooling. Building construction costs per pig space, which includes an outside, covered, in-ground concrete manure storage tank, are expected to be 1.3 to 2 times higher than typical construction of the baseline double wide, fully slatted, tunnel ventilated (TV) barn. These costs are offset by a 3-7% increase in average daily gain and 5-10% decrease in feed consumption per pound of pork produced. Using these assumptions in a standard economic projection, annualized net present value per pig space is between $2.43 and $9.03 with 6.0 to 12.8 years to payback over the TV facility.