Range forage of Vicia variabilis, Astragalus spp., Medicago sativa, Prangos uloptera and Sanguisorba minor was sampled during three phenological stages from the controlled rangeland stations in Chaharmahal and Bakhtiari province, Iran. Samples were analyzed for the determination of Crude Protein (CP%), Ether Extract (EE), Crude Fiber (CF), total Ash, Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF), in vitro Dry Matter Digestibility (DMD) and Organic Mater Digestibility (OMD). Higher and lower values of CP were obtained in vegetative stage of Medicago sativa and seed ripening stage of Prangos uloptera, respectively. The highest and lowest values of EE% were found in Prangos uloptera and Astragalus spp. respectively. The highest and lowest values of CF% were obtained in the vegetative stage of Prangos uloptera and ripening stage of Medicago sativa, respectively. For NDF and ADF, the lower values were found in the vegetative stage of Prangos uloptera and Sanguisorba minor, respectively and higher values were observed in the seed ripening stage of Asragalus spp. and Prangos uloptera. The highest values of DMD and OMD% were obtained in the vegetative stage of Vicia variabilis, but the lowest values were found in Medicago sativa and Sanguisorba minor respectively. Both DMD and OMD% values were reduced from vegetation to seed ripening stage in all the species. It was concluded that it is necessary to pay attention to the seasonal changes in order to conduct the quality study and determine the nutritive value and digestibility of range plants. Use of energy and protein supplement in late period of range plant growth has been recommended for the supply of essential requirements of rangeland animals. پرونده مقاله

Five common range forage including Agropyron intermedium, Bromustomentellus, Hordeum bulbosum, Cousinia bakhtiarica and Scariolla orientalis, weresampled during three phenological stages, from controlled rangeland stations over fivelocations in Chaharmahal and Bakhtiari province, Iran. All samples were chemicallyanalyzed for Crude Protein (CP%), in vitro Dry Matter Digestibility (DMD), OrganicMater Digestibility (OMD), Ether Extract (EE), Crude Fiber (CF), total Ash, NeutralDetergent Fiber (NDF) and Acid Dtergent Fiber (ADF). Results for Crude Protein (CP%)showed significant differences between phenological stages in all of species. Maximum CP(15.2%) was found in vegetation stage of Hordeum bulbosum and the minimum (2.9%)was in seed ripening stage. The CF% was significantly different between phenologicalstages as well as the species. The minimum and maximum values of CF% were found inAgropyron intermedium in Coosinia bakhtiarica, respectively. Similarly, the minimumvalues of NDF and ADF were found in vegetative stage of Scariolla orientalis andAgropyron intermedium respectively, but the maximum values were obtained in seedripening stage of Hordeum bulbosum and Cousinia bakhtiarica. The DMD and OMD%showed slightly reduction passing from vegetation to seed ripening stage in most of thespecies. The highest DMD and OMD% had been observed in vegetation stage of Scariollaorientalis and the lowest were in Bromus tomentellus. It can be concluded that in the earlystage of growth, the quality of forage in range species is adequate for livestockproduction but during that stage, the greatest problem is its lower quantity. By progress ofthe vegetation stage toward the seed ripening stage, the nutritive value of all speciesdecreased thus grazing animals oppose to nutrient deficiencies. پرونده مقاله