Effect of Tannin Content in Horse Bean on Rumen Fermentation in vitro

The objective of the experiments was to demonstrate the influence of low- and high-tannin horse bean on the selected fermentation indicators. The sheep rumen content with the addition of 1, 2 and 5 g of high- and low-tannin horse bean was incubated in vessels of 250 ml volume. A significant increase of ammonia, lactic acid, CO2 and methane as well as pH decrease in samples with addition of horse bean seed was demonstrated. While comparing high- and low-tannin horse bean varieties, it was observed that in the case of small doses of 1 and 2 g a higher intensity of fermentation takes place in the samples with the addition of high-tannin horse bean. In the case of larger doses of 5 g per sample, a higher intensity of fermentation takes place in the samples with the addition of low-tannin horse-bean. A probable reason for the decrease in the fermentation process intensity in the samples with the addition of 5 g of high-tannin horse bean is a high content of tannins, which reduce fermentation processes