The probiotic-prebiotic properties and chemical composition of Yarrowia lipolytica yeast (YL), predisposes it for use as a turkey feed additive. The aim of the study was to determine whether YL in the diet of turkeys would exert more beneficial effect by stimulating antioxidant reactions and increasing mineral availability than Saccharomyces cerevisiae (SC). An additional aim of the study was to test whether the addition of a probiotic bacteria to feed containing Yarrowia lipolytica or Saccharomyces cerevisiae yeast would enhance their effect. The study was conducted on turkeys from seven to 112 days of age to determine the effects of a 3% addition of YL to the diet, as an alternative to the standard SC. It was analysed whether the use of a probiotic (Bacillus licheniformis, Bacillus subtilis) together with yeast would be more effective. Both the yeast (YL or SC) and the probiotic stimulated antioxidant mechanisms (increased CAT; reduced MDA), but the addition of SC was less effective. The inclusion of YL in the feed increased the plasma content of Ca, Mg, Cu, Zn and Fe in the blood turkeys and lowered the content of cholesterol and triacylglycerols. The combined use of yeast (YL or SC) with a probiotic enhances the antioxidant effect while inhibiting of lipid peroxidation. The combined use of yeast with a probiotic can be recommended in cases of stimulation of oxidative reactions (e.g., stress or infection).
Keywords: Yarrowia lipolytica yeast; biochemistry; blood; probiotic; redox; turkey hens.