Diet supplemented with fermented okara improved growth performance, meat quality, and amino acid profiles in growing pigs

This study aimed to assess the efficacy of fermented okara on performance and meat quality, and to explore the feasibility of its partial substitution for corn‐soybean meal in pig production. A total of 48 pigs (Duroc × Landrace × Yorkshire) with an average body weight of 58.60 ± 0.65 kg were randomly assigned to 2 groups, Control group and Fermented okara (FO) group. There were 8 replicate pens each with 3 pigs per treatment. Control pigs were fed a corn‐soybean meal basal diet, treatment pigs were fed a basal diet supplemented with FO throughout the 55‐d experimental period. Results showed that fermentation of okara using probiotics increased its microporous structure, polysaccharides, lactic acid, and free amino acids (FAA) by 46.06%, 150%, and 66.45% compared with unfermented okara, respectively (p < .05). The diet supplemented with FO significantly improved average daily gain (ADG) by 8.70% (p < .01), but decreased the feed gain ratio (F/G) by 5.56% of growing pigs compared to the control diet (p < .05). Furthermore, dietary FO improve meat color, FAA, and the activity of total superoxide dismutase (T‐SOD) and glutathione peroxidase (GSH‐PX) in the serum and muscles (p < .05). Collectively, probiotics‐fermented okara improved growth performance, meat quality and antioxidant capacity, and it can be used to substitute partial corn‐soybean meal in pig industry.