mineral element values of 8 rangeland species in highland pastures of taleghan

to achieve the desired level of animal performance providing animal food supplies containing mineral elements is essential. for this purpose, mineral elements of 8 important rangeland species, including ferula ovina, prangus uloptera, medicago sativa, lotus goeblia, trifolium montanum, melilotus officinalis, sanguisorba minor and stachys inflate, were measured at different growth stages in the summer pastures of taleghan. therefore, at each growth stage 3 samples were taken and for each sample at least five vegetable bases were removed from different vegetation types. data were analyzed using one-way anova and to see the sources of variation within groups the duncan test was utilized. moreover, t-test was used to compare the values of mentioned elements with the critical level to provide the daily requirements of an animal unit in the maintenance mode. the results show that the values of minerals at the early stages of growth are more than those at the final stages of development (seeding stage). moreover, the mentioned values in each stage of the growth are not uniform among the studied species. in general, the studied species are in good condition in terms of the calcium, iron, copper, cobalt and manganese values for meeting the daily needs of animals. however, they are not in optimal condition in terms of the highly consumed elements such as sodium and magnesium values at different growth stages, especially at later stages of growth, for meeting the daily needs of animals. this indicates that the desirability of grassland forage at different times of grazing is not identical regarding the mineral elements. it is normal that depending on the year’s conditions the values of plant mineral elements may change slightly; however, due to the cost of determining mineral elements, the results can be used to estimate the daily animal needs in different years.