Estimation of Nutritive Values of Some Range Species as Indicators for Rangelands Management

Information on different rangeland plants’ nutritive values during various phonological stages is of importance for the rangelands management. This information helps rangeland managers to choose proper grazing times to achieve higher animal performance with no detrimental effects on the rangeland vegetations. Effects of various plant parts’ phenological stages and vegetation types on reserve carbohydrates and forage quality indicators were investigated during 2009 and 2010 in Sabzkooh rangelands at Charmahal province, Iran. Plant samples were collected based on a Completely Randomized Design (CRD) at 3 phonological stages (seedling, vegetative and flowering) with 5 replications. The species included grasses (Secale montanum and Festuca ovina), forbs (Lotus corniculatus and Sanguisorba minor) and shrubs (Kochia prosterata and Salsola rigida). Aerial plant parts’ samples were harvested and oven-dried at 80oC for 24 hours; then, they were analyzed for determining the amounts of Water Soluble Carbohydrates (WSC), Crude Protein (CP), Acid Detergent Fiber (ADF), Dry Matter Digestibility (DMD) and Metabolic Energy (ME). Results showed that forbs contained more WSC as compared to the other two vegetation types (grasses and shrubs). For other forage quality traits (CP, DMD, and ME), there were significant differences between species over two years and higher and lower forage qualities were obtained for forbs and shrub, respectively. For WSC, Sanguisorba minor and Lotus corniculatus had the highest values while Secale montanum and Salsola rigida had the lowest WSC content.