251 Effects of feeding increasing levels of dimethylglycine (DMG) on growth performance, livability, and carcass characteristics of commercial finishing pigs

Abstract

Abstract This study aimed to evaluate the impact of increasing dietary levels of 78% sodium dimethylglycine (DMG) on growth performance, livability, and carcass characteristics of commercial finishing pigs. A total of 1,115 mixed-sex finishing pigs [initial body weight (BW) = 70.1 ± 1.8 kg] were housed in pens with 25 to 27 pigs per pen. Pens within block were assigned randomly to one of four dietary treatments containing 0 (Control), 0.25 (DMG_0.25), 0.5 (DMG_0.5) or 1.0 (DMG_1.0) g DMG/kg of feed with 11 replicates per treatment. This experiment extended over an 8-wk period until pigs were harvested at 125.4 ± 0.8 kg of BW. Data were analyzed using the MIXED procedure of SAS, and preplanned orthogonal contrasts were conducted to evaluate pairwise comparisons as well as linear and quadratic effects related to the increased levels of DMG. While no linear effect was observed, there was a tendency for a quadratic response in closeout feed efficiency (G/F; P = 0.08) and the percentage of pigs with morbidity (P = 0.06), with the most favorable responses found in pigs fed DMG_0.25 (Table 1). Pairwise comparisons between Control and DMG_0.25 treatments suggest that pigs receiving DMG_0.25 showed a 6% increase in closeout average daily gain (ADG; 1.01 vs. 0.95 kg/d; P = 0.02) and a 4% increase in closeout G/F (0.337 vs. 0.324; P = 0.05) compared with those fed Control diet. Furthermore, DMG supplemented at 0.25 g/kg tended to be associated with decreased mortality (P = 0.08), reduced morbidity (P = 0.09) and more pigs sold to the primary market (P = 0.10) compared with Control. In contrast, dietary supplementation of greater concentrations of DMG at 0.5 and 1.0 g/kg were not different compared with Control (P > 0.10). Carcass characteristics, including hot carcass weight, carcass yield, fat depth, loin depth, and fat-free carcass lean, were not different among treatments. The findings of this study suggest dietary supplementation of DMG at 0.25 g/kg of feed enhanced growth performance and livability in finishing pigs. However, feeding greater concentrations of DMG, up to 1.0 g/kg of feed, did not produce different outcomes compared with Control. These results indicate the potential benefits of DMG at specific inclusion rate in optimizing the production and health of finishing pigs.