investigating the effects of salvia mirzayanii essential oil on rumen microbial fermentation and nutrient digestibility using gas production and dual flow continuous culture system

this study was conducted to investigate the effects of different doses of salvia mirzayanii essential oils on gas production parameters, fermentation characteristics using gas production and dual flow continuous culture system. trearments in the gas production experiment was adding 0, 400, 800, 1200, 1600, 2000, 2400 and 4800 mg/l of salvia mirzayanii essential oils to the media. in the second experiment, five 1750-ml dual-flow continuous culture fermenters were used in 3 replicated periods of 9 d. temperature (38.5°c) and liquid and (10%/h) solid (5%/h) dilution rates were kept constant in the fermenters. fermenters were fed daily with 120 g dry matter. treatments arranged as complete randomized block design included levels of essential oils from salvia mirzayanii (800, 1600, 2400 mg/l) and a monensin (0.1 percent of the diet dry matter). addition essential oils of salvia mirzayanii to diet lead to decrease asymptotic gas production, organic matter degradability and biomass. dry matter digestibility and ndf with the level of 800 mg/l essential oil compered to control treatment were significantly increased. concentration of nh3-n was less for pre-feeding (0 h) in treatments with t2 and t3 compared with control treatment. the average of concentration nh3-n was lowest in highest level of essential oils eight hours after feeding. the results showed that using of low level of salvia mirzayanii essential oils could improve nutrient digestibility in the rumen.