The effects of finishing environment on swine performance, pork quality and adipose tissue composition

Brenda Sue Patton, Iowa State University

Abstract

Producers are becoming more aware of product quality as a profit driver in the pork industry. One alternative method is the use of hoop buildings, which are deep-bedded, open-ended, tent-like structures covered with a polyethylene fabric tarp. Several items differ between hoop structures and standard confinement systems, including the use of straw for bedding, increased space allocation, and subjection of animals to seasonal environmental changes. The open-ended design of hoop structures allows greater exposure to temperature changes, with less capacity to maintain a constant temperature as outdoor temperatures fluctuate. The following experiments were designed to ascertain affects between hoop systems to confinement systems. The general hypothesis driving this study was that enrichment of the finishing environment provided by semi-outdoor, deep-bedded finishing systems would allow for lower stress susceptibility, thereby influencing growth response, carcass composition, the rate and extent of pH and temperature decline postmortem, ultimately affecting pork quality attributes perceived by the consumer. Space allocation rates from this study will grant producers using these systems with a standard stocking requirement to efficiently optimize swine growth and pork quality. Hoop-finished pigs were slower growing, with relation to average daily gain and feed conversion capacity than confinement-finished pigs. Hoop pigs also had lower levels of backfat at the 10th rib, less marbling in the loin, and less total lipid in the adipose tissue. The ultimate driver hypothesized for these variations was exposure to ambient temperature fluctuations. Providing more space within hoop systems had small affects on growth, performance, or pork quality attributes. Variations in pork quality were limited to lipid deposition, indicating finishing systems observed in these experiments did not alter product quality. Future research initiatives are necessary to determine specific effects of temperature fluctuation and lipid deposition characteristics in these systems.