Influence of live yeast cells on rumen fermentation and in-sacco dry matter degradability of wheat straw and alfalfa hay by non lactating cows

In this study (latin square design) with four non lactating and rumen fistulated dairy cows were fed a corn silage diet (6.3 kg DM) for 3 weeks supplemented with 0, 3, 6, and 12 g live yeast cells (Saccharomyces cerevisiae; 3.1 * 10(9) cfu/g) per cow and day. The application of yeast cells showed no significant effect on the pH value and the concentration of volatile fatty acids in the rumen. The concentration of NH3-N was significantly increased in case of 3 g yeast cells (p < 0,05). The-dry matter degradability of wheat straw was not affected by yeast supplementation, but dry matter degradability of alfalfa hay increased by about 4 units and 2 units using 3 g and 12 g yeast cells, respectively (p > 0,05).