Soybean meal (SBM) is one of the most important protein sources in swine diets. However, SBM has high concentrations of non-digestible oligosaccharides, mainly stachyose, raffinose, and verbascose, which may increase diarrhea incidence and reduce nursery growth performance. Fermex 200 (Purina Animal Nutrition, Shoreview, MN, USA) is a new source of fermented SBM that may serve as an alternative to other protein sources in diets fed to pigs. However, there are at this point no data for effects of Fermex 200 on growth performance and amino acid (AA) digestibility when fed to weanling pigs.

Therefore, 2 experiments were conducted to test the hypothesis that the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of AA in Fermex 200 are greater than in conventional SBM. The second hypothesis was that Fermex 200 supports growth of weanling pigs as well as other protein sources.

Experimental design

Conventional SBM was sourced from the same batch of SBM used to produce Fermex 200. The conventional SBM and Fermex 200 used in the 2 experiments originated from the same batches. Enzyme-treated SBM (HP 300; Hamlet Protein Inc., Horsens, Denmark) and yeast protein (Proplex DY; ADM Animal Nutrition, Quincy, IL, USA) were also used (Table 1).

Experiment 1: Amino Acid Digestibility

Nine weanling barrows (initial BW: 9.2 ± 1.0 kg) were equipped with a T-cannula in the distal ileum and allotted to a triplicated 3 × 3 Latin square design with 3 diets and 3 periods for a total of 9 replicate pigs per treatment. Two diets that contained cornstarch and conventional SBM or Fermex 200 as the sole source of crude protein (CP) and AA were formulated. A N-free diet was formulated to determine basal endogenous losses of AA. Ileal digesta were collected on d 6 and 7 for each period, and ileal digesta were analyzed for AA to calculate SID of all AA.

Experiment 2: Growth Performance

Two hundred fifty six pigs (initial BW: 6.2 ± 1.0 kg) were allotted to 1 of 4 diets with 4 pigs per pen and 16 pen replicates per treatment. The 4 diets consisted of a negative control diet based on corn and conventional SBM, a positive control diet based on corn, conventional SBM, and enzyme-treated SBM (HP 300), and 2 diets in which Fermex 200 or yeast protein (Proplex DY) replaced HP 300. Pigs were fed the experimental diets in phases 1 and 2, but a common phase 3 diet was provided during the last phase. All phase 1 diets contained 4% plasma, 6.25% whey powder, and 13.5% lactose. Phase 2 diets were similar to phase 1 diets with the exception that no protein plasma and no whey powder were used, and lactose was reduced to 7.5%. The common phase 3 diet was based on corn and conventional SBM.

Results

Experiment 1: Amino Acid Digestibility

No differences were observed between Fermex 200 and conventional SBM for the AID of all AA, total indispensable AA, and total dispensable AA (Table 2). Likewise, SID values for CP and AA were not different between Fermex 200 and conventional SBM.

Experiment 2: Growth Performance

No differences were observed for all growth performance parameters of pigs fed the negative control, positive control, Proplex DY, or Fermex 200 diet (Table 3).

Key points

• The AID and SID values for CP and AA in Fermex 200 were not different from conventional SBM.
• The growth performance of pigs fed diets containing Fermex 200 was not different from that of pigs fed diets containing other protein sources.

Table 1. Analyzed nutrient composition of ingredients (as-fed basis)

¹Fermex 200 = fermented soybean meal (Purina Animal Nutrition, Shoreview, MN, USA).

²HP 300 = enzyme-treated soybean meal (Hamlet Protein Inc., Horsens, Denmark).

³Proplex DY = yeast protein (ADM Animal Nutrition, Quincy, IL, USA).

⁴TIU = trypsin inhibitor units.

⁵ND = not detected.

Table 2. Apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) in Fermex 200 and in conventional soybean meal (SBM), Exp. 1^{1, 2}

¹Data are least squares means of 9 observations per treatment.

²Values for SID were calculated by correcting the values for AID for basal ileal endogenous losses. Basal ileal endogenous losses were determined (g/kg of DMI) as CP, 22.16; Arg, 0.58; His, 0.25; Ile, 0.49; Leu, 0.83; Lys, 0.65; Met, 0.12; Phe, 0.53; Thr, 0.89; Trp, 0.14; Val 0.69; Ala, 0.71; Asp, 1.19; Cys, 0.32; Glu, 1.21; Gly, 1.99; and Ser, 0.69.

³Fermex 200 = fermented soybean meal (Purina Animal Nutrition, Shoreview, MN, USA).

Table 3. Growth performance for pigs fed the experimental diets, Exp. 2¹

¹Data are least squares means of 16 observations for all treatments.

²Proplex DY = yeast protein (ADM Animal Nutrition, Quincy, IL, USA).

³Fermex 200 = fermented soybean meal (Purina Animal Nutrition, Shoreview, MN, USA).