Ehsan Anassori - Department of Clinical Sciences, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
Bahram Dalir-Naghadeh - Department of Clinical Sciences, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
Rasoul Pirmohammadi - Department of Animal Sciences, Faculty of Agriculture, Urmia University, Urmia, Iran
Akbar Taghizadeh - Department of Animal Sciences, Faculty of Agriculture, University of Tabriz, Tabriz, Iran
Siamak Asri-Rezaei - Department of Clinical Sciences, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
Safa Farahmand-Azar - Department of Clinical Sciences, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
Maghsoud Besharati - Department of Animal Sciences, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.
Morteza Tahmoozi - Department of Animal Sciences, Faculty of Agriculture, Urmia University, Urmia, Iran

The effect of inclusion of garlic essential oil (EO) at ۳۳, ۶۶ and ۱۰۰ μg mL-۱, raw garlic (GAR) at ۵, ۱۰ and ۱۵ mg mL-۱ and monensin (MON) at ۷.۵ μg mL-۱ of incubation medium on organic matter digestibility (OMD) was studied with in vitro gas production, ANKOM daisyII and conventional in vitro (IVOMD) methods. The material was incubated with sheep ruminal fluid and the experimental design was a completely randomized design. Cumulative gas production was recorded at ۰, ۲, ۴, ۶, ۸, ۱۲, ۱۶, ۲۴, ۳۶, ۴۸, ۷۲ and ۹۶ hours of incubation. Conventional in vitro OMD was determined after ۴۸ hours incubation in acid and pepsin solutions. Samples for DaisyII OMD prepared according to the operating instructions supplied by ANKOM® Tech. Co., Fairport, USA. Compared to in vitro dry matter digestibility (IVDMD), DaisyII and gas production techniques overestimated (P < ۰.۰۵) OMD. The addition of EO and MON reduced (P < ۰.۰۵) the organic matter (OM), neutral detergent fiber (NDF), acid-detergent fiber (ADF) digestion, and gas production volume. The potential of gas production and rate of gas production for EO and MON were the lowest; however, these variables were higher for GAR supplemented groups. It was concluded that raw garlic could be of great interest for its usage as a modulator of ruminal fermentation.

DaisyII, essential oil, Garlic, Gas Production, Monensin