Effect of yeast Saccharomyces cerevisiae supplementationon serum antioxidant capacity, mucosal sIgA secretions and gut microbial populations in weaned piglets

This study was conducted to determine the effect of different forms of yeasts Saccharomyces cerevisiae supplementation on serum antioxidant capacity, mucosal secretory immunoglobulin A (sIgA) secretions and gut microbial populations in weaned piglets. A total of 96 piglets weaned at 14 d of age were randomly allotted to 4 dietary treatments: (1) basal diet without yeast (Control); (2) basal diet supplemented with 3.00 g kg–1 live yeast (LY); (3) basal diet supplemented with 2.66 g kg–1 heat-killed whole yeast (HKY); and (4) basal diet supplemented with 3.00 g kg–1 superfine yeast powders (SFY).Each treatment had 4 replicates (pens), with 6 piglets per replicate. The experiment lasted for 3 wk. At d 7 and 21 of the experiment, the samples of serum, mucosa and mesenteric lymph node (MLN) from jejunum, and digesta from the ileum and cecum were collected for determinations. Compared with the Control, dietary SFY supplementation increased serum superoxide dismutase (SOD) activity and lysozyme levels at d 7, and jejunum mucosal sIgA secretions at d 21 of the experiment (P