PSVIII-1 Determination of in vitro DM, N and NDF digestibility and fermentability in novel corn co-products for swine

New process technologies are being implemented in the ethanol industry resulting in new high protein corn co-products (HPCP) containing more gross energy and amino acids than conventional distillers dried grains with solubles (DDGS). Thus, estimates of nutrient digestibility for HPCP are needed to assess potential feeding value for swine. Furthermore, yellow dent corn is the predominant grain source in U.S. ethanol and co-product production whereas flint corn is used in Brazil. This study determined and compared in vitro dry matter (DM), nitrogen (N), and neutral detergent fiber (NDF) digestibility and fermentability of U.S. and Brazil corn DDGS and new HPCP. In vitro methods evaluated DM, N, and NDF digestibility and fermentability of 2 corn DDGS samples from U.S. (POET and ICM), 2 DDGS samples from Brazil (BR1 and BR2), 1 corn fiber and solubles sample (CF+S), 3 high protein distillers grains (HP-DDG) samples (BR-HP, US-HP, US-HPG1.5), and 2 HP-DDG samples containing high yeast (Ultramax; UM) and StillPro (SP). Digestibility of DM from hydrolysis varied and was greatest for UM (87.13%; P < 0.001) compared with all other co-products. Fermentability of DM was greater (P < 0.001), and similar for UM (85.6%), SP (76.8%), and US-HP-DDG (72.8%) compared with other co-products. Digestibility of N was greater for UM (91.2%; P < 0.001) compared with all other co-products. NDF digestibility was greater (P < 0.001) for UM (62.5%) and SP (60.5%) compared with all other co-products. POET and ICM DDGS had greater (P < 0.001) DM hydrolysis (78.7% and 68.2%, respectively), than BR1 (37.2%) and BR2 (35.0%) and N digestibility (POET = 65.0%; ICM = 58.9%) compared with BR1 (54.4%) and BR2 (43.4%). These results suggest greater nutritional value for Ultramax and StillPro than conventional DDGS and HP-DDG sources (U.S. and Brazilian) due to greater DM, N, and NDF digestibility.