Gastrointestinal dynamics, immune response, and nutrient digestibility of weanling pigs fed diets supplemented with enzymatically treated yeast.

The objective of this trial was to investigate the effect of enzymatically treated yeast (ETY) on the growth performance, nutrient digestibility, immune response, and gut health of weanling pigs. A total of 192 weanling pigs (6.0 ± 1.04 kg) were allocated to 4 corn and soybean-based diets with increasing concentrations of ETY (0, 1, 2, or 4 g/kg) for a 43-d trial. There were 8 replicate pens (4 replicate pens per sex) and 6 pigs per replicate. The experiment was set up as a randomized complete block design with body weight used as a blocking factor. Pigs had ad libitum access to water and diets for the duration of the study. There was no effect of ETY supplementation on the growth performance indices of weanling pigs. At d 14, there was a quadratic decrease (P < 0.05) in the ATTD of ADF. At d 28, there was a linear increase (P < 0.05) in the ATTD of NDF and a quadratic decrease (P < 0.05) in the ATTD of ADF. On d 14, there was a linear increase (P < 0.05) in serum catalase activity with ETY supplementation. There was a linear increase (P < 0.01) in the gene expression of GPX4 in the ileal mucosa of pigs. Increasing dietary ETY supplementation linearly decreased (P < 0.05) the gene expression of ileal PEPT1. There was a tendency for a quadratic effect (P = 0.07) in the ileal villus height to crypt depth ratio with ETY supplementation. Additionally, there was a tendency for a linear increase (P = 0.06) in ileal digesta butyrate with ETY supplementation. In conclusion, the current study demonstrated that dietary enzymatically treated yeast supplementation could partly ameliorate the deleterious effects of post-weaning stress by enhancing the antioxidative status of weanling pigs. However, prolonged supplementation of ETY may be needed to see its effect on growth performance.