Dry weather across most of the central plains since last fall is creating signals, that a major drought may be on the horizon for this grazing season. The reliance on pasture of most cow herds means that some hard decisions will likely need to be made. The primary decision revolves around feed sources to replace hay or pasture or stretch hay or pasture. Several commodities can be used to replace or stretch hay and pasture; mostly by-products from grain milling.

Two key nutrients are total digestible nutrients (TDN) and crude protein (CP). TDN is the measure of energy used with beef cows, and is the nutrient needed in greatest quantities to maintain performance. CP is the next nutrient needed as far as quantity. Feeds have different concentrations of TDN and CP, and have different costs. Figure 1 illustrates the cost per unit of nutrient of common commodities, which is an effective way to compare feed cost. Hay at $100/ton has the lowest cost per unit of TDN and CP. However, when hay reaches $200/ton, which may happen in severe drought situations especially if trucking long distances, it has the greatest cost per unit of TDN and second greatest cost per unit of CP. Additionally, hay supplies may be limited even if hay is the cheapest source of nutrients.

Currently, corn at $6.50/bu is the least expensive source of TDN followed by soybean hulls at $210/ton and dried distiller’s grains at $280/ton. Dried distiller’s grains is also the least expensive source of CP making it a valuable feed. Therefore, a mixture of corn, soybean hulls, and dried distiller’s grains would be an economically and nutritionally viable option to replace or stretch hay or pasture.

A 1300-lb cow in late lactation requires about 14 lb of TDN and 2.10 lb of CP per day. A mixture of 15% dried distiller’s grains, 20% corn, 35% soybean hulls, and 30% hay fed at 20 lb/day (80% of ad libitum intake) would meet the TDN and CP requirements of the cow. The calf will consume about 4 lb/day of hay or pasture for a total of 24 lb/day. If calves are weaned early at 4 months, 15 lb/day will meet the TDN and CP requirements of an early gestation, dry cow, but then the calf will eat 7 lb/day of mixed ration to gain 2 lb/day for a total of 22 lb/day.

If the price of hay is $100/ton, it is more economical to feed the lactating cow with a nursing calf at $2.11/day, but if the price of hay is $200/ton, it is more economical to wean the calf early and feed a dry cow plus calf at $2.49/day. If the price of hay is $150/ton, then both management options cost the same. This economic calculation is based on the prices of feeds used, and the tipping point will depend upon local hay and commodity prices.

Even though feeding commodities to beef cows and calves can be an economically viable option, it requires the correct management. Feeding large amounts of commodities to beef cows who have full access to pasture or hay will not save much hay and result in greater feed costs. The cost savings is in the fact that less total feed (reduction in hay intake) can be fed to maintain cow performance, which requires limiting access to pasture or hay. It does not require a fenceline feedbunk and mixer wagon. Use the resources you have such as labor, hay intake can be limited by restricting access to the round bale feeder by moving cows in and out of the pen with hay feeders. Early-weaned calves also require more managerial skills in that they are more susceptible to disease and require daily feeding and observation. The rumen of these young calves is not developed enough to effectively digest long-stem hay, and they require moderate energy diet based on grains and commodities to perform well.

Finding alternative feed sources during a drought can be challenging especially if the drought is widespread and hay has to be hauled long distances. Grains and byproduct commodities are viable alternatives that can be used to maintain performance of the cow herd, but feed costs are going to be greater. Additionally, limit feeding moderate concentrate diets to beef cows and managing early-weaned calves requires the correct facilities and managerial skills.

Figure 1. Cost per unit of total digestible nutrients (TDN) and crude protein (CP), and cost per day to maintain 1300-lb cow for common feedstuffs.