Determination of Nutritive Value of Poa trivialis Using in vitro Methods, Gas Production and Nylon Bag

This study was conducted to determine the chemical composition, metabolizable energy, digestibility and ability of gas production of Poa trivialis. Samples was collected at three phenological stages including: vegetative growth, flowering and seedling on two different elevations of 1300 to 1500 m and 2000 to 1800 m asl in Neor and Hir region as the first and second sites, respectively. Testing of gas production was performed using Semi-automatic gas producers machine WT-Binder 87532 Model (made ​​in Germany). Fistulated castrated male sheeps were used for preparation of required rumen fluid. Results show that more crude protein and less cell wall were in the vegetative growth stage. Gas production was higher in the first stage in comparison with other growing stages. The amounts of gas production of soluble and insoluble structures at the first and second sites were 75.63 and 81.50 mL, respectively. Metabolizabe energy of Poa triviali was2.38 in the first site and in the second site 2.48 Mcal/kg DM in the vegetative growth stage. Collected samples from the second site had more metabolizabe energy, digestibility, degradability and gas production in comparison with the results of the first site.