Two experiments evaluated the effects of removing corn DDGS from diets at increasing intervals before harvest on finishing pig performance and carcass characteristics.
For Exp. 1, 985 pigs [PIC TR4×(Fast LW×PIC L02); initially 99 kg BW] were used in a 28-d study. There were 12 pens/treatment and four treatments decreasing in duration of DDGS withdrawal before marketing: 28, 21, 14, or 0 d. All pens were marketed by removing the 17% heaviest pigs on d -21 with remaining pigs marketed at final barn dump (d 0). Overall, there was no evidence for effects of DDGS withdrawal on final BW, ADFI, or G:F (P>0.112); however, as withdrawal time increased, ADG increased (linear, P=0.022) and iodine value (IV) decreased (linear, P=0.001). There was no evidence for differences for HCW or loin depth (P>0.106); however, yield increased (linear, P=0.001) with increasing withdrawal time. Backfat depth decreased (quadratic; P=0.019) and percentage lean increased (quadratic; P=0.033) as DDGS withdrawal time increased.
In Exp. 2, 1,158 pigs (initially 105 kg BW) were used in a 35-d study. There were 15 pens/treatment and four treatments decreasing in duration of DDGS withdrawal: 35, 28, 14, or 0 d. All pens were marketed by removing the 15% heaviest pigs on d -28, the 28% next heaviest pigs on d -14, with final barn dump of approximately 57% of starting inventory (d 0). There was no evidence that final BW, overall ADG, or G:F differed across treatments with increasing DDGS withdrawal times (P>0.116). Overall ADFI increased (linear, P=0.015) as time withdrawn from DDGS increased. Iodine value decreased (linear; P=0.001) and yield increased (linear; P=0.034) with increasing withdrawal time, with no evidence for differences in HCW, backfat, loin depth, or percentage lean (P>0.05).
These experiments suggest that longer withdrawal of DDGS prior to marketing improves carcass yield and decreases IV.