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Considering the quantitative and qualitative limitations of pasture forages for grazing livestock, as well as the lack of plant absorption of mineral elements due to salinity and drought stresses, lack of organic matter, and high soil pH in most regions of the country, there is a lack of mineral micronutrients in grazing livestock in the country, which can be mainly reflected in the reduction of livestock production and reproductive performance. One of the basic methods for increasing productivity in grazing livestock is to prepare maps of the status of livestock mineral elements for different climatic regions and use them to adjust and manufacture mineral supplements specific to each region. For this purpose, by studying and inquiring about the final reports of research projects, student theses, and articles presented in reputable domestic databases, data on mineral elements of the forages grazed by livestock, soil physicochemical data, and clinical, tissue, and performance evidence related to mineral elements in livestock were collected, along with recording the geographical coordinates of each data. Then, by comparing the data of mineral elements with the standard recommended values (NRC, 2005, 2007), the status of each element in terms of critical deficiency, borderline deficiency, normal value, borderline excess, and critical excess was determined in each region and displayed on the map with separate colors through the GIS location information system. The nutritional mineral elements studied included eight elements: calcium, phosphorus, magnesium, potassium, iron, zinc, copper, and manganese, and the areas explored included 14 provinces: Ardabil, Isfahan, Alborz, Ilam, Bushehr, Khorasan, Khuzestan, Semnan, Fars, Kurdistan, Kerman, Golestan, Lorestan, and Markazi from three cold, temperate, and warm climates. The results showed that there is marginal and critical deficiency of phosphorus in three cold, temperate and warm climates, marginal deficiency to marginal excess of calcium, magnesium and potassium, and critical to marginal deficiency of zinc in cold and temperate climates, normal to marginal excess of copper and manganese in warm and temperate climates, marginal to critical excess of calcium and iron in all three climates and marginal to critical excess of copper in cold climates. In the studied areas, the highest frequency of deficiency was related to phosphorus and zinc and the highest frequency of excess was related to iron and manganese. Therefore, it is recommended to adjust mineral supplements for grazing livestock based on the mineral element status map.
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