Feed ethanol byproducts right
By Dr. Jim White

With more ethanol production on the way, DDG will find its way into more rations. Be careful how you feed it. Not all byproducts are created equal.

As the ethanol industry expands, so will the availability of the ethanol byproduct, dried distillers grain. The byproducts will vary in nutrient content, so producers should plan accordingly, seek nutrition advice and measure the nutrients of the byproducts they feed.

When making recommendations on feedstuffs, there are a number of things to consider. Certainly two of the most important criteria are cost and nutrient content. While these are crucial, they are not the only considerations to cover.

To use a non-ethanol byproduct example, consider cheese whey. Evaluated strictly on cost and nutrient content, liquid whey from a cheese plant is a real feeding champ. And to really skew the math, let’s assume that you can get the whey at no cost—if you pick it up. Free is good, and he who spends the least wins, right?

Yet there are reasons we all don’t scramble for liquid whey. There are factors other than feed cost to consider: transportation, storage, shrink, handling, consistency, facilities, livestock health risks, etc. The health risk for cheese whey is salt poisoning, which can be avoided by increased water intake. But increased water intake lowers whey intake. And cheap gain was the point, right? So let’s agree that rations are more complicated than cost alone.

Now back to evaluating ethanol byproducts. Remember, moisture content is crucial. The actual moisture content is important, but so is the variation in the moisture. Moisture will have a huge effect on feedstuff value. As rough rules consider: 1) The wetter the feedstuff, the greater the shrink. 2) As variation becomes greater, lower the inclusion rates.

Feeding in ethanol’s wake
The biggest users of ethanol byproducts have been beef feedlots and large dairies. For them, the sticky nature of wet distillers grain is helpful in encouraging palatability, conditioning the ration and reducing sorting. Likewise, wet distillers grain is considered as having greater energy and protein value than dried distillers products. However, the wet material has some limitations. Handling and storage are concerns. Wetter feeds often will have longer mix times and may require additional equipment and labor to deliver. If a producer can’t use a trailer per week, he is not likely to be a wet byproduct candidate. The material is that perishable.

There have been efforts to mix the wet byproducts with forages and pack them in a silo, keeping the pile airtight. Usually 200 pounds or so of grass hay or corn stalks are used. It works if you make sure to seal the pile or bag completely. If air gets in, the mixture molds and deteriorates. It does not “ensile” per se (in silage, water-soluble carbohydrates are fermented to lactic acid). I stress: keeping air off the pile is the key to success.

If you are using less than 15 percent of the diet dry matter as distillers product, I generally evaluate the use on the cost of the product and the nutrient content of the material in question. Using 15 percent or less is usually the call when distillers are used as a protein source.

DDG as protein
Distillers grain will have more non-degraded protein than other protein sources. It will not help you raise the soluble protein level in the diet. When using more than 15 percent of the diet’s dry matter as distillers grain, you begin to use the distillers as an energy source against corn. If distillers grain is the same price as corn and has three times the fat, the question is how much you can use. About a third of the dry matter is the upper, prudent limit. That’s not to say that the nutrition police will send you to jail for feeding higher levels than a third of the dry matter.

But if that’s your plan, I’d check out the 2007 Nebraska Beef Report. It had a trial by that compared distillers grain in beef diets at percentages of 0,10, 20, 30, 40 and 50. The researchers ended up dropping the 50-percent treatment as calves were dying from toxic levels of sulfur.

Increasingly, reports of sulfur-related polioencephalomalacia (bovine polio) are emerging in DDG-based diets—particularly when the ration has 0.4 percent or more sulfur. Cerebrocortical necrosis is a synonym for polioencephalomalacia.

Confusion sometimes arises because the term polioencephalomalacia is used in two ways. It can mean a brain lesion lacking specific causation. Or it can mean a neurological syndrome caused by disturbed thiamine status. There is a tendency to assume that the polioencephalomalacia is caused by altered thiamine status because cattle respond to thiamine, sometimes even though tests to assess thiamine status were not performed.

The sulfur level in the feed becomes even more problematic if the livestock water is high sulfate water (greater than 300 parts per million). This might be reported as 300 mg/liter on water lab reports.

Fat limits
The fat content in distillers grain tends to limit the upper use level too. Higher fat levels, particularly shorter fats such as corn oil, have resulted in lower fiber digestibility of ruminant diets. The high fat tends to result in flowability issues, too. While distillers grain often doesn’t flow well, it doesn’t pellet well either.

Other considerations
Aflatoxin levels can be concentrated in the distillers grain, usually two to three times higher than the level in the base grain. Ethanol production does not degrade aflatoxin the same way as ammonization or roasting.

Any given ingredient will not by itself meet an animal’s nutrient requirements; ethanol byproducts will have adequate protein, energy, potassium and phosphorous. They may have excessive sulfur, and they will be deficient in the other macro minerals. If you need a source of starch or fermentable sugar, DDG is not a good choice. DDG fits much better if you are looking for fermentable fiber and protein, say on mature warm-season grasses or corn stalks. DDG would not fit well if you want to supplement a young cool-season grass pasture. Such a pasture is soluble protein long and starch short, Cattle Charge or hand fed Cadence would be better options.

Help with feeding DDG
As a cattle protein source, DDG is used with confidence at under 15 percent of the diet. And as an energy source, the higher use rates means producers should be concerned about sulfur levels, bovine polio and rumen fermentation. Do not use at rates higher than a third of the dry matter.

Using heavy DDG means being ready to supplement with starch if needed. You should certainly plan to add minerals and vitamins to the diet. MFA DDG Completer is a good source of complementary minerals and vitamins. If soluble protein is needed, MFA Cattle Co-Mixer is the better product choice. If in doubt, call Jim White, (573) 876-5256, or your MFA feed salesperson.

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