Effect addition of the peppermint oil to barley straw in some characteristics of fermentation in the rumen, in vitro digestibility and metabolic energy

Abstract

Abstract This study aimed to investigate the influence of adding different concentrations of peppermint oil to barley straw in some fermented rumen features, in vitro digestibility and energy of metabolism. The results showed a significant decrease (p<0.01) in the pH of all treatments except T4, during all incubation period in comparison with the control treatment. The results also presented a significant increase (p<0.01) in the concentration of the nitrogen of ammonia in treatments of T3 and T4 and during every part of incubation periods in comparing with the control treatment. Additionally, a significant decrease (p<0.01) was discovered in the in vitro dry matter, digestibility organic substances and metabolic energy compared with the treatment of control.