The winter feeding season for grazing animal livestock farms is nearing.
It is appropriate to remind readers about the stillage product available from The Green River Distilling Company in Owensboro. They have proven to be a reliable source of by-product nutrition for regional farms as several have been consistently using the stillage for more than three years.
With the supply steadily increasing with the distillery capacity expansion, more will have the opportunity to adopt feeding stillage to beef herds transitioning from pasture-based diets to stored feed. Distillers grain is a product that can supplement the nutrition of poor quality hay and extend stored hay supplies.
It can be fed to beef cattle as both an energy source and protein supplement. The moisture content, fat levels, and sulfur concentration can limit recommended feeding rates. Supplementation of low-quality fescue hay can be accomplished at rates of 20-30% of the diet dry matter with minimal impact on fiber digestion.
Distillers grains are available in several forms, depending on the source. The product available from Green River is called whole stillage. As much water as possible is screened off and the thicker whole stillage goes out as feed.
The dry milling process of distilleries is very similar to traditional feed mills. Grains are received at the plant and ground through a hammer mill. The ground grain is sent to a tank, combined with water, and the temperature and pH are increased to an environment suitable for enzymes to convert the grain starch to smaller sugars.
This conversion is known as mashing. The mash temperature is increased to kill off wild yeast and other microorganisms which may decrease the product yield.
The mash is then cooled for the enzymes and yeast which metabolize the sugar to alcohol and carbon dioxide during fermentation. This fermented mixture of yeast, alcohol, and spend grain is known as “beer.”
After the fermentation period, the beer is sent to the distillation area where it is heated, volatilizing the alcohol, and leaving behind spent grains and water known as stillage. Excess water is screened off and the product is available for feeding to livestock.
Corn is comprised of two-thirds starch which is easily fermented by yeast to alcohol and carbon dioxide. There is limited utilization of other nutrients in corn in the fermentation process which results in a three-fold increase of concentration in the stillage for feed.
For example, on a dry matter basis, the average crude protein of corn is near 9%. Corn-based distillers grains are near 30%. Fat increases from 4% to 12% and phosphorus increases from .3% to .9%. The nutrient content of distillers grain classifies these sources as both high protein and high energy alternatives.
The nutrient profile of distillers grains does result in the need for caution. When feeding moderate rates of distillers grain, the mineral supplementation program will need to be modified.
The high level of phosphorus will cause an imbalance in the calcium to phosphorus ratio. Using a low to 0% phosphorus mineral supplement that is also 20% or greater in calcium will help achieve proper calcium to phosphorus ratio.
If a mineral of this type is not used, the addition of feed grade limestone or calcium carbonate is required to balance the calcium to phosphorus ratio. The inclusion rate of limestone is low and less than 2% of the total diet dry matter.
Feed grade limestone is inexpensive and adds little to the overall diet cost. Also, as yeast die-off during fermentation the pH level increases. Therefore, it’s important to feed sodium bicarbonate to prevent bloat.
In most situations, the level of protein in the distillers grain product eliminates the need for other protein sources. Recent research has demonstrated that diets containing distillers grain perform similarly to diets containing other sources of protein such as soybean meal or urea.
Use of soybean meal for lightweight calves and starter feeds to meet individual amino acid requirements may be necessary, but a portion of diet protein can come from distillers grain.
For more information, the Cooperative Extension publication Distillers Grain Coproducts for Beef Cattle is available at the Extension Office or online at http://www2.ca.uky.edu/agcomm/pubs/asc/asc186/asc186.pdf. For information on the availability of Green River Distilling Company distillers grain, contact the distillery at (270) 691-9001.