Drought Management Strategies
for Beef Cattle

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Johnny Rossi and Robert Stewart
Extension Animal Scientists

Drought conditions are a yearly occurrence in Georgia and every cattleman should have a plan in place to minimize the effects of drought on the farm’s finances. Drought conditions can cause several problems such as reduced pregnancy rates, lower milk production which lowers weaning weights, and loss of body condition of the cow, which leads to a higher supplementation bill in the winter. Animals must be supplemented with purchased feeds if adequate animal performance is going to be achieved. Supplemental feeding will add to the cost of production. Therefore, supplemental feed costs need to be kept as low as possible and feed purchased should be kept to a minimum.

Evaluate stocking rates

If grass runs out every time there is a dry spell, you are probably overstocked. Grass should only completely run out when there is a long term drought. If there is a large quantity of low quality forage available after a long drought, the farm is probably understocked.

Nitrates

Nitrate toxicity is a concern when grazing drought stricken pastures fertilized heavily with nitrogen. The only way to know if there is a potential problem is to test the forage.

It is safe to graze cattle on forages that have 5,000 or less ppm nitrates. Forages most likely to be toxic are millet, sudangrass, sorghum x sudangrass hybrids, and corn. Do not put hungry cattle on potentially toxic forage as they can consume high amounts of nitrates in a short period of time. Feed the cattle hay before turning them onto the pasture, or introduce the pasture slowly by grazing only a couple of hours each day. Wait for at least five days after a rain before turning the cows onto a pasture with high nitrate levels.

Deworm

Parasites can reduce cow performance and rob your cows of expensive supplemental feed. Cows will graze closer to the ground when forage is in short supply, which can increase the number of parasites ingested. Deworming now will reduce the chance for reinfection because of hot dry weather and also reduce the number of parasites in the pasture next year.

Culling

The most often used method for reducing feed needs during a drought is to sell a portion of the herd. Consider pregnancy testing and culling cows that are open, old and low producers, and that calve late in the calving period. This will provide more feed for younger, more productive cows.

Early weaning calves

Most cattle producers in Georgia market calves at weaning time. Weaning weights are almost always negatively affected during a drought situation. Producers can either sell calves at younger ages, wean and feed calves separately from cows, or supplement the cow herd with stored or purchased feeds. Dry cows in early to mid pregnancy are at their lowest in terms of nutritional requirements. These cows can be maintained on poor quality forages with little or no supplemental feed.

Early Weaning

1. A dry cow will require about 30 to 40 percent less energy and 50 percent less protein feed than a lactating cow.
2. Cows that you plan to cull after calves are weaned can be culled now. This will reduce the amount of feed needed. The normal culling rate is approximately 15 to 20 percent each year. Culling combined with early weaning will cut the feed needed for cows by at least half.
3. In addition, low producing dry pastures may be enough to maintain cows that have had their calves weaned. Maintaining cow and calf pairs on dry pasture will result in very calf low growth rates as well as lowered body condition scores and conception rates in cows.
4. Improved conception rates. Early weaning the calf at 120 days of age or less has been shown to greatly improve conception rates when grazing the same forage as cows that continue to nurse their calves. In addition, cow body condition is improved when calves are early weaned, and cows will require less supplemental feed in the fall and winter to regain body condition.
5. Calves can be fed higher quality supplemental feeds, and calf weights will not be decreased at seven months of age, which is the time calves would normally be weaned. Early weaned calves are extremely efficient, often requiring 4 to 5 pounds of feed per pound of gain when fed a high grain diet.

Rations for early weaned calves

Pasture or hay without any supplemental feed will not work for early weaned calves. Calves will not gain enough weight to justify early weaning. Calves that are early weaned can be fed a typical high grain feedlot ration. Rations for calves that are early weaned should contain 70 percent or greater TDN and 16 to 18 percent protein. The protein level can be lowered to 13 to 14 percent when calves weigh 450 pounds. Researchers at Oklahoma State University have used a diet of 45 percent corn, 30 percent cottonseed hulls, 18 percent soybean meal, 4 percent molasses, 2 percent calcium carbonate, 0.5 percent dicalcium phosphate, 0.5 percent trace mineral salt, and Vitamin A for calves weaned as early as six to eight weeks old. Calves should consume 3 to 3.5 percent of body weight of this ration once they are adapted to the diet. Include an ionophore (Rumensin® or Bovatec®) to reduce digestive disorders and improve feed efficiency.

Creep feeding

If early weaning is not an option, then creep feeding is an excellent alternative. The most profitable time to creep feed is during a drought. A mixture of 75 percent grain and 25 percent soybean meal can improve gains by 0.5 to 1.0 pound per day. Another widely used creep feeding option is 100 percent soybean hulls or a mixture of 50 percent soybean hulls and 50 percent corn gluten feed.

Feeding cows grain-based diets

If pasture is depleted after the cow herd is culled, then supplemental feeding will be necessary. Hay is the most often used option, but certainly not the only option. Grains and by-product feeds are often cheaper per unit of energy than hay. This is especially true during a drought situation when there is a lot of competition for any available hay. Several research studies have shown that limit feeding high grain rations based on grains or by-products will successfully maintain a dry cow. The grain mix (14 percent protein) is usually fed at 1.2 to 1.5 percent body weight. At least 4 pounds of hay or a roughage such as cottonseed hulls should be fed to maintain normal rumen function. A lactating cow will require about 30 percent more feed than a dry cow. Limit feeding grain supplements requires a high level of management, and producers can seek help from their local extension agent with implementing this management practice.

Another option is to feed a grain/roughage mix free-choice. The rations generally contain 50 percent roughage such as peanut hulls, cottonseed hulls, or hay. The grain portion (50 percent of diet) should contain at least 15 percent protein for lactating cows and 12 percent for dry cows. A few examples for the grain mix are 85 percent corn and 15 percent soybean meal, 50 percent corn gluten feed and 50 percent soyhulls, and 60 percent corn and 40 percent whole cottonseed. Many by-product feeds and grains can yield acceptable performance. The local county extension agent can help formulate a free-choice ration.

Grouping cows

It is important to group cows by nutrient needs, such as production status (dry vs. lactating), age, and body condition. Grouping cows can avoid over or under feeding a particular group, which will reduce supplemental feed costs. Pregnant cows may lose body condition when grazing drought stressed pasture. Therefore, body condition score cows at least 60 days prior to calving and adjust ration to ensure cows are at least a condition score of 5 at calving time.

Supplements for forage

Many producers may be feeding hay or have limited grazing available. Adequate nutrition can be achieved by supplementing energy, protein, minerals, and Vitamin A. The following supplements can be considered.

1. Range cubes - They require no feed troughs, are convenient, but expensive. Feeding 3 to 5 pounds per day is generally recommended. However, more can be fed if needed.
2. Liquid Supplements, molasses blocks, and protein blocks - These are convenient, but expensive. Daily consumption will generally be less than 2 pounds. Liquid supplements provide supplemental protein but will not provide enough supplemental energy. Cows should be fed 3 to 5 pounds a day of supplemental energy.
3. Grain, by-products - A mix of 75 percent corn and 25 percent soybean meal can be fed at 3 to 5 pounds per day to maintain animal performance. By-product feeds such as soyhulls, citrus pulp, corn gluten feed, wheat middlings, cottonseed, and distillers grains can provide economical sources of protein and energy. These feeds are equal in energy to corn when fed as a supplement to a forage-based diet. A disadvantage to using by-products is that some operations may not have storage facilities and most by-products must be purchased in truck load lots to be economical. However, several producers can purchase a portion of a truck load to ease this problem. For smaller quantities, producers may want to store feed in a gravity flow wagon or store feed in large bags that can hold up to a ton of feed. It will have to be handled by hand to feed but may be the only economical feeding method available. These by-products vary widely in protein and feeding recommendations, so, you may want to ask your local county extension agent for help when balancing rations using by-products.
4. Self-Fed Supplements - Rations containing a protein supplement with salt can provide 2.5 to 3.5 pounds of supplement per cow per day when fed fair quality hay free-choice or limited grazing. The supplement should consist of one-third each of corn, cottonseed or soybean meal, and salt. Reduce salt to 20 percent for an intake of 4.5 to 5.5 pounds per day. Approximately 10 to 15 percent of the salt should be in the form of trace mineral salt and the remainder can be plain white salt. Do not use trace mineral salt as the only salt source as a trace mineral toxicity could occur. Be sure plenty of fresh water is available when feeding salt limited diets. Use limited supplement intake with salt only with mature cows. Cows will vary in their consumption of salt and the salt level may need to be continually adjusted during the feeding period. Provide Vitamin A at the rate of 7,000 International Units per pound of feed (14 million units per ton). Cattle should be hand-fed for one week prior to self-feeding in order to adjust to these rations.

Summary

Culling priorities should start with open cows first, old cows second, and low producers third. Early weaning can greatly reduce feed costs and allow cows to maintain a body condition score of 5, which should lead to optimal (> 90 percent) pregnancy rates. Calves weaned earlier than normal require a nutrient dense diet that must be either a grain based diet or high quality forage such as ryegrass plus a grain supplement at approximately 1 percent of body weight. A variety of supplements can be used to replace a portion of the forage needs during a drought. When the forage supply is exhausted, limit fed grain based diets are an economical, effective solution to feeding cows.

Bulletin 1323/December, 2006

The University of Georgia and Ft. Valley State University, the U.S. Department of Agriculture and counties of the state cooperating. Cooperative Extension, the University of Georgia College of Agricultural and Environmental Sciences, offers educational programs, assistance and materials to all people without regard to race, color, national origin, age, gender or disability.

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