Effects of dietary level of distillers dried grains with solubles (DDGS) and pig removal program at harvest on the growth performance, carcass characteristics, and fat quality of growing-finishing pigs

Abstract Text: The effect of increasing dietary level of distillers dried grains with solubles (DDGS) and pig removal program at harvest on growth performance, carcass characteristics, and fat quality of growing-finishing pigs was evaluated in a study carried out on a commercial wean-to-finish facility.  A randomized complete block design was used with 6 treatments: 1) 0% DDGS; all pigs in pen sent for harvest at one time (1 group); 2) 0% DDGS; pens sent for harvest in 6 groups over time (6 groups); 3) 20% DDGS; 1 group; 4) 40% DDGS; 1 group; 5) 40% DDGS; 6 groups, 6) 60% DDGS; 1 group.  A total of 1,632 pigs housed in groups of 34 were used.  Diets were fed from 23.4 ± 1.15 kg to 128.9 ± 1.91 kg for pens sent for harvest as 1 group.  For pens sent for harvest in 6 groups, the heaviest pigs were taken off test at a pen mean BW of 112.1 ± 2.04 kg; subsequently, the heaviest pigs were taken off test every 7 d.  At harvest, 1 barrow and 1 gilt/pen close to the pen mean were selected for fat quality evaluation.  Increasing DDGS inclusion level linearly reduced (P ≤ 0.001) ADG, ADFI, and carcass yield, but had no effect (P > 0.05) on G:F and 10^th rib backfat thickness.  Iodine value increased (P ≤ 0.001) with increasing DDGS level for belly fat, jowl fat, and backfat.  Variation in body weight at harvest, and ADG and G:F were lower (P ≤ 0.01) for pens sent for harvest in 1 compared to 6 groups.  Carcass yield was lower (P ≤ 0.001) for pens sent for harvest in 6 compared to 1 group.  There was no effect (P˃ 0.05) of pig removal program on fat iodine value.  These results suggest that increasing dietary levels of DDGS increases fat iodine value; however, sending pigs for harvest in 1 compared to 6 groups has no effect on iodine value.

Keywords: Pigs, DDGS, Iodine Value