Iron availability varies widely with iron source.Įstimated iron requirements for steers have been increased by the NRC from 10 ppm (1976) to 50 ppm (1984). Iron present in soil often is unavailable to either plants or animals thus, no mapping of soil or plant iron levels has been attempted. As a result, regulatory authorities have placed a maximum use level on the amount of EDDI that can be included in ruminant diets. However, there is no scientific evidence substantiating the use of EDDI for those treatments. Some nutritionists have incorporated EDDI into diets as a preventative or cure for foot rot and soft tissue lumpy jaw. Castrated animals may require less iodine than do females, and females less than intact males.Ī commonly used source of iodine in feeds is ethylenediaminedihydroiodine (EDDI). Under cold stress, the turnover rate of iodine increases, which may increase the need for dietary iodine. Requirements for iodine vary with cattle breed and age of animals. Goitrogenic plants of wide renown and ill repute include those of the cabbage family, although goitrogens are also found in soybean meal, cottonseed meal and rapeseed meal. Plants from low iodine soils have low iodine concentrations. Iodine deficiency An iodine deficiency in cows decreases metabolic rate and causes goiter. Corn-, milo- or wheat-based feedlot diets contain very little iodine and they all need iodine supplementation. The estimated iodine requirement for growing cattle is. In addition, certain plants contain goitrogens that inhibit the use of iodine and increase its requirement. Iodine is deficient in soils of plants across much of the Northern U.S. Adequate copper is needed by the immune system, so a copper deficiency may cause animal health problems. High levels of sulfur, molybdenum, calcium and zinc each reduce absorption of copper and thereby increase its dietary requirement. Young animals absorb copper more extensively than adult animals. Soil and plant copper concentrations vary. Elevated levels of copper from copper sulfate may act as an antibiotic to depress ruminal fermentation. With a severe copper deficiency in cows, pigmentation of hair is reduced so that red cattle become yellow and black cattle become gray. With milo-based diets, one need not be concerned about copper, but with corn-based or wheat-based feedlot diets, 2 to 3 ppm of copper needs to be added. When mineral supplements designed for cattle are fed to sheep, toxicities can occur. In contrast, the tolerance level for sheep fed a low molybdenum diet is only 8 to 11 ppm. The new values are more similar to NRC (National Research Council) dairy requirements.ĭietary copper is tolerated by cattle at levels up to about 115 ppm. The estimated requirement for copper by growing beef cattle was increased from 4 ppm in 1976 to 8 ppm in 1984. Cattle or feed from these areas may be deficient in copper. Copper deficiency in cows also can occur in certain areas of the U.S., which have an excess of molybdenum, such as the Southwest, Florida and Central Texas. Soils or plants in the upper Midwest, along the West Coast, in Florida and along the East Coast in the Virginia-Maryland area are low in copper. Soil types vary in their cobalt level, and grasses are generally higher in cobalt than legumes. As cobalt is a component of vitamin B-12, its requirement might increase with higher levels of propionate production in the rumen. Vitamin B-12 often is included with vitamins A and D in injections for newly received cattle. Injections of cobalt or vitamin B-12 can stimulate the appetite of certain animals for horses, B-12 injections are common. 02 ppm and must have cobalt supplemented.Ĭobalt deficiency One of the first signs of cobalt deficiency in cows is a decreased appetite. Cobalt levels calculated to be present in typical feedlot diets composed of corn, milo and wheat are. If cattle or feeds are obtained from these regions, deficiencies will be more likely. Moderate and extreme cobalt deficient areas for cattle exist primarily in the Central, Northeast and Southeast sections of the U.S.
This TDN excerpts an article by Oklahoma State University animal nutritionist Fred Owens which identified the geographic availability of trace minerals 1. Ranchers and feedlot operators need to know whether or not these minerals are available in their regions and supplement deficiencies accordingly. Cobalt, copper, iodine, iron, manganese, selenium and zinc are trace minerals important to good cattle nutrition. A complete, quality mineral program positively impacts fetal development, immune function, bone development, nervous system function, fertility, muscle development, milk production, and skin, hair and hoof quality.
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