Evaluation of swine liquid feed system with corn - ethanol co-products

Abstract

Two experiments were conducted to evaluate the use of ethanol co-products, wet distillers grain (WDG) and condensed distillers soluble (CDS), in a swine liquid feeding system. The first experiment was conducted to evaluate the concentration of DE and ME and the apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of energy and nutrients in WDG and CDS fed to growing pigs. Six dietary treatments were studied by replacing 15% and 30% of a corn soybean meal basal diet with WDG or a mixture of WDG or CDS. The experiment consisted of 10 days of adaptation and 4 days of sample collection. Our results indicated that digestibility of 15% CDS diet was significantly higher (P < 0.05) compared to 30% WDG diet. DE and ME were higher in CDS compared to WDG. There was no significant difference in amino acid AID of diets. Lysine AID value of WDG was 75% which was higher than reported DDGS values. CDS lysine AID was 58%. Higher lysine AID could be because WDG was not exposed to drying, which reduces lysine digestibility in DDGS. The second experiment was conducted to determine the ratio of WDG to CDS on the performance of wean to finish pigs fed via a computer-based automatic liquid feeding system. Four dietary treatments were compared by replacing 20% DDGS in the basal diet with same percentage (20%) of WDG or combination of WDG and CDS. Treatment 1, 20% DDGS, Treatment 2, 20% WDG, Treatment 3, 17% WDG + 3% CDS, and Treatment 4, 14% WDG + 6% CDS. The experiment was conducted from 2 weeks post-weaning to finishing (126 days on trial), using a 5-phase feeding rogram. The overall ADG was 0.912, 0.934, 0.957, and 0.937 kg/d, ADFI on a dry matter basis 2.47, 2.2, 2.26, and 2.24 kg/d, and gain to feed ratio 0.33, 0.37, 0.38, and 0.37, for Treatments 1 to 4, respectively. Overall ADG was higher (P = 0.05) in Treatment 3 compared with the DDGS group. Overall, pigs fed diets containing WDG and/or CDS (Treatments 2, 3, and 4) had lower (P = 0.001) ADFI but higher G:F (P = 0.001) compared with animals fed the control diet containing 20% DDGS. Thus, WDG and the combinations of WDG and CDS have beneficial effect on growth performance compared with DDGS.