Evaluation of FSP (Fermented Soy Protein) to Replace Soybean Meal in Weaned Pigs: Growth Performance, Blood Urea Nitrogen and Total Protein Concentrations in Serum and Nutrient Digestibility

A total of one hundred and forty four weaned pigs with an average BW of $8.09{\pm}0.05$ kg were used in a 28 day study to investigate the effects of fermented soy protein on growth performance, blood urea nitrogen and total protein concentrations in serum and nutrient digestibility in weaner pigs. Pigs were blocked by initial body weight and randomly allocated to one of four dietary treatments in a randomized complete block design. There were six replications per treatment. Dietary treatments included: SBM (corn-soybean meal basal diet), F 5, 10 and 15 (fermented soy product was used at 5, 10 and 15% to replace soybean meal in basal diet, respectively). ADG (average daily gain) and ADFI (average daily feed intake) were not affected (p>0.05) by dietary treatments during the entire 4-wk study period. There were linear increments in feed efficiency (p<0.01) as the dietary FSP level increased during the entire feeding period. No significant differences were observed for dry matter and nitrogen digestibility during the experimental period (p>0.05). Digestibilities of histidine, lysine and methionine were increased as the FSP level increased (linear effect, p<0.05, p<0.01). Among non-essential amino acids, alanine, glutamic acid, serine, tyrosine and total non essential amino acid digestibilities were increased linearly (p<0.05, p<0.01). There were quadratic effects in protein digestibility (p<0.05). Total amino acid digestibility of the F15 diet was improved compared with the F5 diet (p<0.05). There were no significant differences in fecal consistency score among the treatments (p>0.05). At the end of experiment, BUN (blood urea nitrogen) concentration was increased as the FSP level increased (linear effect, p<0.01) and total protein concentration was lowest (p<0.05) for pigs fed the SBM diet among treatments. In conclusion, the feeding of 10 or 15% FSP to nursery pigs improved feed efficiency, amino acid digestibility and blood urea nitrogen and total protein concentrations in blood.