Beef cattle in Georgia, like anywhere else, need the right minerals for strong growth and good reproduction. Choosing the correct mineral supplement is key to keeping your animals healthy and productive. While quality forages and grains can supply many of the necessary minerals, a well-chosen supplement fills the gaps without overdoing it. This guide provides a comprehensive overview of mineral nutrition for beef cattle in Georgia, focusing on forage and feeding programs to help you select the best supplement for your herd. It’s not about pinpointing the “most popular” breed; it’s about ensuring every breed thrives with the right mineral balance.
Beef cattle grazing in a lush pasture
Understanding Macrominerals
Macrominerals are essential minerals found in the animal’s body at levels greater than 100 parts per million (ppm). Beef cattle require calcium, magnesium, phosphorus, potassium, sodium, chlorine, and sulfur for optimal health.
Calcium and Phosphorus: The Bone Builders
Calcium and phosphorus are critical for skeletal health. Ninety-nine percent of total body calcium and 80 percent of total body phosphorus are stored in the bones. These minerals are also vital for weight gain, efficiency of gain, and milk production during lactation. A phosphorus deficiency can delay puberty in heifers and negatively impact heat cycles in mature cows. The ideal Ca:P ratio is about 1.5:1, with a range of 1:1 to 4:1 considered acceptable.
Most grasses are adequate in calcium, and legumes like alfalfa and clover are excellent sources. However, corn silage and sorghum silage are poor sources. Concentrates are generally poor calcium sources, except for citrus pulp. Corn, corn by-product feeds, and sorghum grain necessitate calcium supplementation.
Forages tend to be low in phosphorus, particularly late in the growing season. Phosphorus deficiencies are more likely during winter when cattle consume dry forages. Concentrates contain moderate to high concentrations of phosphorus.
Sodium and Chlorine: Nerve and Muscle Function
Sodium and chlorine, commonly known as salt, are essential for nerve and muscle function. They regulate body pH and water retention. Deficiencies lead to appetite loss and inefficient weight gain. Sodium is often deficient in diets, while chlorine levels are usually adequate. Cattle consume 0.005 to 0.010 percent of their body weight as salt daily.
Magnesium: Preventing Grass Tetany
Magnesium is essential for enzyme function, the nervous system, and carbohydrate metabolism. A deficiency can lead to grass tetany, a serious metabolic disorder, especially in cows grazing lush fescue or small grain pastures during late winter and early spring. A mineral mixture containing 10 to 14 percent magnesium oxide, consumed at 4 ounces per day, can prevent grass tetany.
Potassium: Maintaining Balance
Potassium plays a role in acid-base balance, osmotic pressure, and water retention. Grasses, especially lush spring growth, provide adequate potassium for grazing cattle, so supplementation is rarely needed.
Sulfur: Protein Component
Sulfur is a component of essential amino acids. A deficiency is unlikely under normal feeding conditions, but excess sulfur can interfere with copper metabolism.
Understanding Microminerals
Beef cattle require 10 microminerals, with copper, zinc, and selenium being the most likely to be deficient in grazing diets.
Cobalt: Vitamin B-12 Production
Cobalt functions as a component of vitamin B-12, synthesized in the rumen by bacteria. Deficiency leads to loss of appetite and poor growth.
Copper: Enzyme Systems
Copper is a common micromineral deficiency. It’s an important component of enzyme systems. Deficiency signs include reduced fertility, depressed immunity, and hair discoloration. Supplement with copper sulfate, tribasic copper chloride, or an organic complexed form.
Iodine: Thyroid Hormones
Iodine is essential for thyroid hormone function, regulating energy metabolism. Deficiency can cause goiter in newborn calves.
Iron: Hemoglobin Formation
Iron is required for hemoglobin formation. Deficiency symptoms include anemia, depressed immunity, and decreased weight gains.
Manganese: Reproduction
Manganese is required for normal reproduction, and fetal and udder development. Deficiency is rare in Georgia.
Selenium: White Muscle Disease Prevention
Selenium deficiency can cause white muscle disease in newborn calves and increase susceptibility to calfhood diseases.
Zinc: Immunity and Hoof Health
Zinc is often deficient in Georgia forages. It’s a component of many enzymes and is important for immunity, male reproduction, and skin and hoof health.
The Role of Vitamins
Vitamins are closely linked to mineral metabolism and absorption.
Vitamin A
Vitamin A is important for healthy skin and mucous membranes. Requirements are usually met by grazing fresh, green grass, but stored feeds should be supplemented with vitamin A.
Vitamin D
Vitamin D aids the absorption of calcium and phosphorus from the intestine and their deposition in bone.
Vitamin E
Vitamin E is usually present in sufficient quantities; however, a selenium deficiency could lead to an apparent deficiency of vitamin E.
Selecting the Right Mineral Supplement
Test your forages for mineral content to guide your supplement choices. Consider these points when purchasing minerals: calcium to phosphorus levels, salt level, bioavailability (particularly copper), level of “trace minerals,” and additives.
Grain-Based Diets
Supplements for grain-based diets should contain about 25 percent calcium. Supplemental salt should be provided. The primary microminerals of concern are zinc, copper, cobalt, and selenium.
Factors Affecting Mineral Intake
Mineral intake can fluctuate. Monitor intake and adjust mineral feeder placement as needed. Adding salt can reduce overconsumption, while adding palatable feedstuffs can improve under-consumption.
Mineral Feeders
Ensure an adequate number of feeders are available for the stocking rate of the pasture. Place feeders near water, in shaded loafing areas, and near the best grazing areas.
Supplement Form
Loose mix minerals are most desirable for brood cows. For cattle on complete diets, minerals are best supplied when mixed in a TMR.
Bioavailability Matters
Consider the bioavailability of mineral supplements. Sulfates and chlorides are generally more bioavailable than oxides. Organic minerals can be more effective in certain situations.
Identifying Deficiencies
Mineral deficiencies can be difficult to diagnose. Rule out other possible causes of poor performance, monitor mineral intake, and evaluate trace mineral levels and sources.
Copper Deficiency: A Growing Concern
Copper deficiency is an increasing concern in Georgia. Sulfur antagonisms are a common cause.
By understanding these essential aspects of mineral nutrition, you can tailor your supplementation program to meet the specific needs of your beef cattle, regardless of breed, ensuring optimal health and productivity in Georgia’s diverse agricultural landscape.
