In recent months, a shortened supply of distillers grains has reduced the amount many cattle producers have access to and increased the price of available distillers grains, according to a University of Nebraska-Lincoln "BeefWatch" post by Karla H. Jenkins.
Jenkins, a cow/calf systems and stocker management specialist at the university, said this has led many producers to evaluate what their supplement options are.
According to Jenkins, cow/calf producers should not simply substitute corn for distillers grains fed to bred beef cows. "Typically, the reason production cows are supplemented is that they are consuming poor-quality hay or range and need protein supplementation to support the microbes in the rumen so the microbes can digest the forage," she said. "Corn contains approximately 70% starch. Starch has a negative impact on the rumen microbes needed to digest poor-quality forages. So, unless an additional source of nitrogen (which comes from protein) is also fed, the cattle will likely perform poorly if corn were substituted for distillers grains."
Jenkins noted that acceptable substitute supplements for distillers grains depend on the class of livestock fed, the basal diet available and the desired animal performance. She said cattle producers may want to ask extension beef specialists or educators for ration balancing assistance for each class of livestock to ensure that substitutions meet animal requirements.
If pregnant, non-lactating, 1,200 lb. cows are in the last trimester of pregnancy, they would require about 1.86 lb. of crude protein and 12.6 lb. of total digestible nutrients (TDNs) per day, Jenkins said. If those cows were grazing unlimited dormant winter range, then supplementing 6.5 lb. per cow per day of an alfalfa that contains 18% crude protein would meet the cows’ need for protein and energy, she suggested.
Jenkins also noted that urea-containing supplements will also supply rumen microbes with the necessary nitrogen, and the resulting performance in gestating beef cows is acceptable when readily digestible structural carbohydrates are not limiting.
Forage testing hay or grass used for the basal diet will help producers determine the actual amount of supplement needed in order to minimize overfeeding expensive supplements, Jenkins added.
Economics. Looking at current costs in Nebraska, Jenkins noted that distillers grains generally contain 30% crude protein and 108% TDNs in forage-based diets. Assuming that a producer can obtain distillers grains — but at a higher cost than previously purchased — she said if a producer has to pay $195 per ton for dried distillers grains bought and delivered, the cost on a dry matter basis is $221.59 per ton, assuming 12% moisture. Therefore, a ton of crude protein from the dried distillers grains costs $738.64 on a dry matter basis, Jenkins calculated.
If a producer bought an alfalfa hay tested at 18% crude protein as a protein supplement and paid $185 per ton delivered, that alfalfa costs $215.12 per ton of dry matter, or $1,195.09 per ton of crude protein, Jenkins said.
She concluded that while distillers grains cost more than in previous years, they still are a more cost-effective protein supplement than the alfalfa hay alternative used in this example. Producers should evaluate all alternatives based on nutrient content and include any associated transportation and feed delivery costs, Jenkins said.