Effect of fermented protein feedstuffs on pig production performance, nutrient digestibility, and fecal microbes

In order to determine the availability of fermented protein feedstuffs (FPFS)-such as cottonseed, blood, and feather meals-with Aspergillus oryzae, 2 phases of feeding experiments were adopted for 7 weeks. Sixty 58-day-old crossbred pigs were assigned to 6 groups, 10 pigs per group. Group 1 was the control; groups 2, 3, and 4 were supplemented with 6%-7%, 12%-14%, and 18%-21% FPFS, respectively, by replacing the same percentage of soybean meal (SBM); group 5 was supplemented with 12%-14% unfermented protein feedstuffs (UFPFS) by replacing the same percentage of SBM; group 6 was on the same base as group 3 with digestive energy (DE) balanced as in group 1. The results showed: (1) The soluble amino acids in FPFS were increased by 211% (58.06 vs. 18.68 g/kg), compared with UFPFS; (2) the average daily gain (ADG) increased (P < 0.05) in group 2, compared with the other groups; ADG in group 3 was higher than that in group 5 (P < 0.05); and (3) nutrient digestibility in the groups supplemented with FPFS was higher than in the group supplemented with UFPFS (P < 0.05). The results suggest that a 6%-7% FPFS supplementation to replace SBM in pig diets would be ideal and economic.