A total of 695 mixed sex growing-finishing pigs (600 × 241, DNA; initially 242.7 ± 1.36 lb) were used in a 14-d trial to determine the effects of feed withdrawal before the first and final marketing event on carcass weight, carcass yield, and economics. Pens of pigs were assigned to 1 of 3 treatments in a randomized complete block design. There were 24 pens per treatment and 9 or 10 pigs per pen. Treatments consisted of none, 6, or 12 h of feeder closure prior to loading pigs on the truck at both the first (2 weeks before final marketing) and final marketing to achieve approximately 12, 18, and 24 h of feed withdrawal prior to harvest at the processing plant. There was no evidence of differences (P ≥ 0.10) for ADG, ADFI, or F/G during the 14-d period between the first and final marketing event. However, pig BW at time of loadout, with 24-h of feed withdrawal prior to harvest were lighter (P < 0.05) than those with only 12 h of feed withdrawal both at first marketing event and the last. Pigs that had access to feed (12 h withdrawal prior to harvest) gained weight during the marketing day, while pigs with 18 or 24 h of feed withdrawal lost weight. For carcass characteristics, pigs at final marketing with 12 h feed withdrawal prior to harvest had increased (P < 0.05) HCW compared to those with 24 h feed withdrawal. There was a tendency (P = 0.055) for a treatment effect with pigs undergoing 12 h feed withdrawal prior to harvest having a 1.1 lb heavier HCW than those with 24 h feed withdrawal. When evaluating carcass yield, using live weights for all pigs 24 h prior to harvest, pigs in the final marketing group with 12 h of feed withdrawal prior to harvest had greater yield (P < 0.05) than those marketed with 24 h of feed withdrawal. However, when evaluating carcass yield using live weights 12 h prior to harvest for the final marketing and overall, pigs marketed at 24 h of feed withdrawal had greater yield (P < 0.05) than the other two treatments. Conversely, in the first marketing event, pigs with 12 h of feed withdrawal had decreased yield compared to pigs with the 18 and 24 h of feed withdrawal treatment. There were no differences in backfat, loin depth, and lean % between
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