Effect of Saccharomyces cerevisiae dried yeast on the meat performance traits and selected indicators of humoral immunity in lambs

The aim of this study was to determine the effect of Saccharomyces cerevisiae on indicators of meat performance traits in sheep as well as on selected non-specific indicators of humoral and cellular defense. The experiment was performed on 32 suckling Kamieniec lambs divided into two equal groups (control and experimental). Over a period of 60 days, experimental group of lambs were fed a diet supplemented with Saccharomyces cerevisiae dried yeast (the yeast supplement did not change the value of the feed ration). The following meat performance indicators were determined: body weight, daily gains, growth rate, the dimensions of musculus longissimus dorsi sections, skin and subcutaneous fat thickness and fat thickness over the loin "eye" area. Selected indicators of non-specific humoral immunity (lysozyme activity, ceruloplasmin activity, total protein and gamma globulin content) were determined in the blood serum of lambs. Compared to control, yeast administered to the experimental group of lambs significantly increased the values of the analyzed meat performance traits i.e. body weight, growth rate, musculus longissimus dorsi dimensions (P ≤ 0.05) and daily gains (P ≤ 0.01), pointing to improved muscle development. Lambs fed the yeast showed a significant (P ≤ 0.01) increase in lysozyme and ceruloplasmin activity and increased serum concentrations of gamma globulins. Significant differences between the experimental and control groups were not observed only with respect to the serum concentrations of total protein. Suuplementing the lambs' feed with yeast had a positive effect on meat performance traits and indicators of humoral immunity.