By Karla Wilke, Extension cow/calf an Range Management Specialist
Temperatures dropping below 15 F in early October may have put some sugarbeets in western Nebraska at risk of decaying at the crown. When decay begins, the beet becomes unacceptable for sugar production for human consumption.
Sugarbeets not fit for human consumption can be an economical source of feed for beef cattle. Producers should be aware, however, of how sugarbeet nutrient content compares to other common feeding rations such as corn and beet pulp, and also how the rotting process affects the beets’ nutrient quality.
In a University of Nebraska research trial, gestating cows performed similarly when their rations were changed to replace 20% of the corn with sugarbeets. When growing calves were fed 44% sugar beets (dry matter basis), they were more efficient than calves receiving corn. In a finishing diet, however, when sugarbeets replaced corn up to 15%, cattle had reduced performance compared to 0% sugarbeets.
When sugarbeets begin to rot, sugars are lost rapidly. Analyzed for water-soluble carbohydrates, rotting sugarbeets were found to contain only 26.9%, compared to 73% in fresh chopped beets. Fat-soluble carbohydrates were 22.7% in rotting sugarbeets compared to 69.5% in fresh chopped beets.
Therefore, mixing chopped rotting sugarbeets with straw or poor-quality hay as soon as possible will help reduce sugar loss. An effective method is mixing 10% poor-quality roughage and 90% sugarbeets (on an as-is or actual pounds basis) and packing in a bunker or ag bag.
The nutrient quality of chopped sugarbeets is different from that of sugar beet pulp, the by-product of sugar production. Sugarbeet pulp has a crude protein content of 10%, while sugar beets will likely be 4.5%. The neutral detergent fiber content of sugarbeet pulp is about 45%, compared to only 15% in sugarbeets, making the beet a more comparable substitute for corn in the diet than a fiber source.
A protein source such as distillers grains or alfalfa would need to be included in a diet with a mixture of poor quality hay or residue and rotting sugar beets. The amount of sugar left in the rotting sugar beet will vary, but assuming they have lost 10% of their original sugar, and mixed with residue or poor hay in the proportions mentioned above, then the mixture could have a total digestible nutrients (TDN) value of about 64%.
For help developing diets with chopped sugar beets, contact University of Nebraska Extension personnel.