<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>The objective of the present study was to investigate dose-response effects of the essential oil (EO) and dry extract (EX) of <italic>Satureja khuzistanica</italic> (SK) on <italic>in vitro</italic> gas production kinetics, rumen fermentation, ruminal methanogenesis and microbial protein synthesis. So, EO and EX were tested at 0 (as control); 150 (low dose); 300, 450 (intermediate doses) and 600 mg/L (high dose). The gas produced over 24 h of incubation (GP<sub>24</sub>) decreased linearly with both EO and EX dosages (P&lt;0.01). <italic>In vitro</italic> methane production was reduced by both EO (14–69%, depending on the included dose) and EX (7–58%). Microbial protein (MP) as well as the efficiency of microbial protein synthesis (EMPS) were improved by EO (18.8–49.8% and 20.4–61.5% for MP and EMPS, respectively) and to a lesser extent by EX (8.3–25.7% and 4.6–24.2% for MP and EMPS, respectively). Ammonia concentration was dropped in linear and quadratic manners with EO (P&lt;0.05), and linearly with EX dosages (P&lt;0.01). EO and EX exhibited depressive effects (in linear and quadratic (P&lt;0.05), and linear manners (P&lt;0.01), respectively) on total protozoa count. A mixed linear and quadratic effect was observed from both EO and EX on total VFA concentration (P&lt;0.01). Total VFA concentration increased at 300 mg/L of EX, but decreased at high dose of both EO and EX. The acetate proportion increased with EO intermediate and high dosages, but it decreased at the expense of propionate at low and intermediate doses of EX. In total, these findings confirmed previous research on the great capacity of plant-based feed additives in positively modulating rumen fermentation that their effects may vary depending on the doses used. Specifically, these results suggest that EO and EX have high potentials to improve rumen functions at intermediate doses, which needs to be confirmed by <italic>in vivo</italic> experiments.</p>
</abstract>

The objective of the present study was to investigate dose-response effects of the essential oil (EO) and dry extract (EX) of Satureja khuzistanica (SK) on in vitro gas production kinetics, rumen fermentation, ruminal methanogenesis and microbial protein synthesis. So, EO and EX were tested at 0 (as control); 150 (low dose); 300, 450 (intermediate doses) and 600 mg/L (high dose). The gas produced over 24 h of incubation (GP24) decreased linearly with both EO and EX dosages (P<0.01). In vitro methane production was reduced by both EO (14–69%, depending on the included dose) and EX (7–58%). Microbial protein (MP) as well as the efficiency of microbial protein synthesis (EMPS) were improved by EO (18.8–49.8% and 20.4–61.5% for MP and EMPS, respectively) and to a lesser extent by EX (8.3–25.7% and 4.6–24.2% for MP and EMPS, respectively). Ammonia concentration was dropped in linear and quadratic manners with EO (P<0.05), and linearly with EX dosages (P<0.01). EO and EX exhibited depressive effects (in linear and quadratic (P<0.05), and linear manners (P<0.01), respectively) on total protozoa count. A mixed linear and quadratic effect was observed from both EO and EX on total VFA concentration (P<0.01). Total VFA concentration increased at 300 mg/L of EX, but decreased at high dose of both EO and EX. The acetate proportion increased with EO intermediate and high dosages, but it decreased at the expense of propionate at low and intermediate doses of EX. In total, these findings confirmed previous research on the great capacity of plant-based feed additives in positively modulating rumen fermentation that their effects may vary depending on the doses used. Specifically, these results suggest that EO and EX have high potentials to improve rumen functions at intermediate doses, which needs to be confirmed by in vivo experiments.

Dose-response effects of the Savory (<italic>Satureja khuzistanica</italic>) essential oil and extract on rumen fermentation characteristics, microbial protein synthesis and methane production <italic>in vitro</italic>

Department of Animal Science, Faculty of Agriculture

Department of Animal Science, Campus of Agriculture and Natural Resources

Annals of Animal Science

This work is licensed under the Creative Commons Attribution 4.0 International License.

Dose-response effects of the Savory () essential oil and extract on rumen fermentation characteristics, microbial protein synthesis and methane production 

The objective of the present study was to investigate dose-response effects of the essential oil (EO) and dry extract (EX) of Satureja khuzistanica (SK) on in...

Dose-response effects of the Savory (Satureja khuzistanica) essential oil and extract on rumen fermentation characteristics, microbial protein synthesis and methane production in vitro

Published Online: Jul 19, 2022

Page range: 1001 - 1014

Received: Jul 26, 2021

Accepted: Oct 11, 2021

DOI: https://doi.org/10.2478/aoas-2021-0084

Keywords
essential oils, feed additives, gas production, microbial protein

© 2021 Mostafa Mehdipour Golbotteh et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Dose-response effects of the Savory (Satureja khuzistanica) essential oil and extract on rumen fermentation characteristics, microbial protein synthesis and methane production in vitro

Published Online: Jul 19, 2022

Page range: 1001 - 1014

Received: Jul 26, 2021

Accepted: Oct 11, 2021

DOI: https://doi.org/10.2478/aoas-2021-0084

Keywordsessential oils, feed additives, gas production, microbial protein

© 2021 Mostafa Mehdipour Golbotteh et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Keywords
essential oils, feed additives, gas production, microbial protein