Deficient and Excess Minerals in Forage in the United States

IN MANY PARTS of the world, symptoms of malnutrition or disease in livestock on certain areas have been traced to deficiencies of nutritionally essential mineral elements in the available forage. In some of these areas, before the causes of the difficulties were discovered and remedial measures taken, there were serious economic losses as the result of impaired productive capacity and death of animals. Such deficient areas have been known for some years to exist in the United States, and the question of mineral deficiencies in forages has at one time or another been investigated by many of the State experiment stations. As a result of the cooperative w^ork of several bureaus of this Department and some of the experiment stations, a toxic condition that is sometimes fatal to livestock in certain of the Great Plains and w^estern mountain States has been found to be caused by consumption of native forage (and also grain) containing excessive quantities of selenium. In order to assemble for the Yearbook information on areas in each State where mineral deficiencies or excesses in the forage have been found to produce symptoms of malnutrition in livestock, a form letter requesting information bearing on this problem was sent to