In a previous study it has been shown, that adding Yea-Sacc1026 in diets with high percentage of voluminous forage, improves the digestibility of organic substance from 78.93% to 92.05% after 48 hours of fermentation [1]. The highest coefficient of digestion for the organic substance with or without yeast has been obtained with a barley proportion of 40%: 86.87% after 48 hours of fermentation without yeast and 89.95% with yeast. The rate of digestion was rapidly influenced by adding Yea- Sacc1026 in forage diets and has an impact on the fodder consume and is therefore a method of improving the performance of the animals. This study has observed the productive parameters (body weight, daily medium growth), as well as the effect of yeast Saccharomyces cerevisiae, Yea-Sacc1026 strain, on them. In the first 12 days of the experiment, the daily medium growth was 250 g/day for the control lot and 263 g/day at the experimental lot. During the entire period of the experiment, the daily medium growth was significantly higher (p<0.02) at the experimental lot EL, 196 g/ day, in comparison with the control lot WL, 170 g/day. The variance is 7.86% at the EL lot and 16.38% at the WL lot.