Abstract

The objective of this study was to evaluate the effects of different levels of aromatic plants (AP);“Origanum onites L. (ORE), Rosmarinus officinalis L. (ROS) and Schinus molle L. (SHN)” on in vitro gas production (GP), organic matter digestibility (OMD) and net energy lactation (NEL) using an in vitro gas-production method. Two rumen-fistulated sheep were used in the experiment. The sheep were fed with 60% of alfalfa hay and 40% of concentrate feed twice daily. Five different levels of ORE, ROS, and SHN were added to the concentrate (CON) to produce 200 mg KM (C - without , AP; 1 - 0.02 mg AP + 198 mg CON; 2 - 0.04 mg AP + 196 mg CON; 3 - 0.06 mg AP + 194 mg CON; 4 - 0.08 mg AP + 192 mg CON; 5 - 0.10 mg AP + 190 mg CON). The volume of gas produced was recorded at 2, 4, 8, 12, and 24 h after incubation. The results showed that, GP, OMD and NEL contents decreased significantly as the level of ORE, ROS, and SHN added to CON increased. It was concluded that, ORE, ROS, and SHN are potential supplements that alter rumen fermentation. To obtain exact results, the findings obtained under in vitro conditions should be supported by in vivo studies.

Key words: Ruminant, aromatic plants, feed digestibility, gas production, organic matter digestibility.