مقايسه ارزش غذايي مهمترين گونه هاي مرتعي نيمه استپي گرم استان خوزستان

Comparison of nutritional values of important range species in semi warm steppe Rangeland of Khouzestan

Awareness about forage nutritional values of range species in different stages is necessary for range forage management. In order to evaluate nutritional values of six important range plant species: Astragalus gypsicolus.Astragalus sieberi,Medicago polymorpha, Medicago laciniata, Onobrychis gypsicola, Hyparrhenia hirta at two phenological stages (Vegetative growth and full flowering) the study carried out in semi warm steppe rangeland of Khouzestan. The samples were dried and then the important nutritional parameters: crude protein, erude fiber, ADF, digestible dry matter, metabolisable energy, ash, phosphorus and calcium were measured. The split plot experiment at random complete block design was used for data analysis and the mean values were compared using Dunkan Test. The results showed that the forage quality in all of species were higher in vegetative growth than full flowering stage. Amount of crude protein, digestible dry matter, metabolisable energy, ash, calcium and phosphorus were decreased with development of growth but amont of crude fieber and ADF were increased. The highest percentage of crude protein and the lowest percentage of ADF obtained in Astragalus gypsicolus but the lowest percentage of crude protein and the highest percentage of ADF were in Hyparrhina hirta. The DMD in range legumes were %63.4 to %75.8 but in the only range grass under study was %42.