This year's growing conditions have led to a lot of lightweight barley. As a result, it may pay to work barley into traditional corn diets for feeder cattle, not only to reduce costs but also to ensure a supply of grain.
Despite barley's widespread use as a feed grain, there are a number of concerns about feeding it. There are many misconceptions and contradictions about it as well.
Some assume that barley is inferior in quality to corn, but that may not always be true. The National Research Council (NRC) lists corn with a total digestible nutrient (TDN) value of 90% (NEg of 1.55 Mcal/kg). Barley's TDN value is ranked at 88% (NEg of 1.40 Mcal/kg).
Variation In Barley
However, different varieties of barley have shown equal or higher values of net energy compared to corn. This was pointed out by Jan Bowman of Montana State University and confirmed by other university research.
Nutrient values for corn are similar, regardless of the region, the environment and the variety — except for some specialty varieties. Meanwhile, barley shows tremendous varietal, agronomic and physical (test weights) differences.
NRC separates barley grain into Pacific Coast barley, barley grain and lightweight barley (less than 38 lbs./bu.). R.L. Preston's “2001 Feed Composition Guide” (February BEEF, page 10) lists values for barley grain, barley grain 2-row, barley grain 6-row and light-weight barley (42-44 lbs.).
This wide variation in barley nutrient values — of which energy is the most important criterion — is also evident in a number of university and private research. These wide variations in energy values may partially explain the success or failure with feeding barley. It would seem important to know the variety of the barley fed, but this is generally not possible with purchased grains.
Light test-weight barley is another perplexing question. Most people heavily discount lightweight barley without really knowing the true feeding value. Some research and my personal observations have shown lightweight barley to have a similar feeding value to 48-lb. barley in some cases. But that's not always true.
Lightweight barley typically has a higher protein value but lower energy content. Often, this barley is a malting type rejected for lacking “plumpness,” but feed barleys may also be included.
Several years ago, I submitted client samples of 50- and 38-lb. barley (variety unknown) for analysis. As expected, the values for protein and acid and neutral detergent fiber were all higher for the lighter barley.
The values for percent starch and gross energy for the lighter barley were slightly higher than for the heavier barley, however. The gross energy values do not necessarily reflect the net energy of the samples.
I wouldn't expect this to always be the case, but this illustrates the wide discrepancies in the value of barley in feeding trials.
On the other hand, feeding barley presents more management problems than feeding corn. There are more acidosis and bloat problems with barley, and barley can't be fed whole. It must be processed before feeding to get good results.
Barley has a fibrous hull that must be broken or dissolved before the starch is made available. The barley kernel is also smaller than corn, so cattle tend to swallow it whole rather than chew and break the hull.
In most cases, steam rolling hasn't been shown to increase performance. In fact, it may reduce performance over dry rolling. Barley starch is more rapidly digested than corn, and steam rolling may increase the incidence of acidosis.
Barley should only be slightly cracked or broken into two pieces. Fines are a problem with dry rolling and may make the ration more dusty and less palatable.
Watch For Bloat, Acidosis
Bloat is a major concern when feeding barley, and it may be increased when feeding alfalfa hay. Cattle need to be eased gradually onto a barley diet.
Once adapted, feed must be available to them constantly so they don't become hungry, over-eat and then become bloated or suffer from acidosis.
When feeding high levels of barley, wheat or even corn, use a combination buffering system of sodium bicarb and magnesium (MgO). The bicarb buffers the rumen, while MgO buffers the small intestine where a lot of acidosis takes place.
Extra calcium (limestone) may also be used, but keep the calcium to phosphorus ratio below 8:1 or performance may suffer. Excess MgO is excreted and shouldn't present a digestive problem as with high-calcium diets.
Generally, barley will replace corn in most growing diets without a loss of performance or efficiency. Many times, cattle will stall-out at 145 days on an all-barley diet. So, keep this in mind when feeding calves longer than 145 days.
David Wieland is a Shepherd, MT-based nutrition consultant specializing in cow/calf, feedlot and horses. For more information on his subscription newsletter, call 406/373-5512 or e-mail at [email protected].