Evaluation of Saccharomyces cerevisiae fermented Moutai distiller's grains as an alternative ingredient for growing-finishing pigs.

Three experiments were conducted to evaluate the effects of incorporating Saccharomyces cerevisiae fermented Moutai distiller's grains (FMDG) into diets for growing-finishing pigs across three body weight (BW) phases: 30 to 50 kg (Exp. 1), 50 to 75 kg (Exp. 2), and 90 to 130 kg (Exp. 3). The experimental diets were corn-soybean meal based with 0%, 5% or 10% FMDG. Metabolomic analysis revealed that fermentation enriched FMDG with beneficial compounds, including carbohydrates, quercetin, and tripeptides, compared to unfermented Moutai dried distiller's grains. Results form the animal experiments showed that dietary inclusion of FMDG at levels up to 10% did not adversely affect growth performance in any phase. Notably, 5% FMDG inclusion during the later finishing phase (90 to 130 kg) significantly increased (P < 0.05) average daily feed intake (ADFI) and numerically improved average daily gain (ADG) and feed conversion ratio (FCR), reducing meat production cost by 0.54 RMB/kg. Apparent total tract digestibility (ATTD) of nutrients varied by phase, with enhanced crude protein and calcium utilization at 30 to 50 kg but reduced (P < 0.05) calcium digestibility at 90 to 130 kg. In later finishing pigs, inclusion of 5% and 10% FMDG significantly decreased (P < 0.05) serum endotoxin, diamine oxidase, and interleukin-6 levels. We further confirmed that dietary inclusion of FMDG increased (P < 0.05) the expression of tight junction proteins including claudin-4, occludin, and zonula occludens protein-1 (ZO-1) in the jejunum. Carcass traits and meat quality were maintained or improved, with increased (P < 0.05) loin eye area and meat redness (a*) in the 5% FMDG group. Overall, these findings demonstrate that FMDG can be effectively included at up to 10% in swine diets without compromising animal health and performance, with 5% FMDG providing particularly beneficial for later finishing pigs due to its positive impacts in improving feed efficiency, carcass traits and meat quality, as well as enhancing intestinal integrity.