Whenever feed costs have gone skyward, feed formulators look to the option of using alternative ingredients, points out Dr Nick Dale, poultry science department, University of Georgia, Athens.

But he points out there are very few materials of either plant or animal origin that have not been tried as feed ingredients at some place or time.

“This is not to say that new ingredients do not occasionally arise, although any such ingredients are usually only available in limited supply on a local basis,” says Dale.

He says what has occurred over the past several decades is that the abundance and generally favorable pricing of corn and soybean meal have led to a situation in which other ingredients, which may have been widely studied, have been largely overlooked. By-products of the biofuel industry, catfish meal and pearl millet are among ingredients now in the spotlight. Bakery meal and animal protein meals, while sometimes considered alternative ingredients, are so widely used that they hardly merit designation as alternatives.

Because there are very few ingredients not already known to the industry, Dale says nutrient compositions for alternative ingredients can be found in standard tables of ingredient composition and in scientific literature. “However, such ingredients are often produced in relatively small facilities with variations in manufacturing procedures. A frequent result is that the same ingredient may vary markedly in nutrient composition when procured from different sources,” Dale cautions. 

He points to dried distillers grains plus solubles (DDGS) as a prime example, currently produced at more than one hundred and twenty locations in the U.S. “The protein content of meals from these plants varies from less than 26 to over 29 percent. If variation of this magnitude were to exist in soybean meal, the high and low protein samples would not even be sold as the same ingredient,” he notes. Samples from potential suppliers of any alternative ingredient should be evaluated against standard nutrient profiles as an initial step before incorporation.

Dale also cautions that almost all ingredients have some aspects warranting attention prior to their use and these attributes are often the limiting factors for maximum inclusion in the animal diet.

“Alternative ingredients should always receive full consideration for use in feed formulas, not only in times of elevated prices,” sums up Dale. 

“However, new sources of any ingredient should be submitted for laboratory evaluation prior to purchase and use in formulation, and possible limitations considered.” He says it is questionable whether significant savings will be realized from the use of alternative ingredients. Although special relationships can sometimes be developed between supplier and feed manufacturer, prices of ingredients of similar nutrient content almost always rise and fall in tandem.