Effect of Pen Space Allowances on Growth Performance of Finishing Pigs

Available floor space allocation recommendations are based on considerably lighter market-weight pigs than currently in the United States (i.e., ~130 kg). Therefore, the objective of this study was to investigate the effects of individual floor space allocation on overall growth performance and carcass characteristics of pigs raised to >135 kg. Over 49 d, three floor space per pig allocations were tested: 0.88, 0.75, and 0.61 m²/pig. When the average weight of pigs in the barn reached 135 kg, the heaviest pigs from each pen were marketed in four cuts, approximately one week apart. Overall, weekly feed disappearance per pig, the mean body weights of pigs, and gain:feed was not affected by floor space allocation (<i>p</i> > 0.10). Pigs remaining in pens with 0.61 m²/pig tended (<i>p</i> < 0.09) to be lighter after the first cut than pigs raised with 0.88 m²/pig. However, there was no difference in body weight between the floor space allocations when the final group was marketed (143.9 ± 0.6 kg; <i>p</i> = 0.13). Carcass lean percent tended (<i>p</i> = 0.08) to be greater (56.8 vs. 56.4%) from pigs provided 0.61 m²/pig of floor space.