Low-phytate corn may be a remedy for animal waste concerns

Poultry and swine producers in environmentally sensitive areas around the world know the headaches of animal waste handling. Dutch producers are even taxed for the levels of manure their hogs generate. Could it happen here? It's possible. That's why more livestock producers are showing interest in low-phytate corn.

Low-phytate corn may not be the answer to all manure-handling problems, but it can help reduce phosphorus levels. "That's where its main value lies," says Alex Fink, consultant with Context Consulting, West Des Moines, IA, and coauthor of a study of quality traits.

Most phosphorus in corn is in a salt form (phytate) that is indigestible by monogastric animals. It passes through the animal and results in high phosphorus concentration in manure.

Animals need phosphorus for bone development, so producers must supplement rations with digestible phosphorus. However, because low-phytate corn contains more digestible phosphorus than conventional corn contains, producers may replace supplements with low-phytate corn. Use of the low-phytate corn will lighten the phosphorus load in the environment, which will be important if government agencies broadly mandate phosphorus levels in the future.

Ready for spring planting. Several seed companies are now testing low-phytate corn. ExSeed Genetics LLC, Owensboro, KY, will be the first company to make low-phytate corn available for spring planting in 1999. ExSeed is releasing NutriDense LP and Yellow Dent LP in limited quantities. (For more information, contact the company's Web site at www.exseedgenetics.com.)

Kim Kuebler, ExSeed's director of marketing, says ExSeed was one of a handful of companies that signed a license with the USDA's Agricultural Research Service to insert the trait into corn genetics.

University of Illinois poultry feeding trials have shown that ExSeed's low-phytate corn contains 84% digestible phosphorus, says Kuebler. Available phosphorus in standard yellow dent corn is about 28%, Kuebler notes. Hybrids containing the low-phytate trait from other companies will likely be commercialized in 2000.

Pioneer Hi-Bred International is currently evaluating yield data on two corn products but eventually intends to offer low-phytate hybrids in all maturities, says Linda Wyss, Pioneer product manager, corn feed traits.

Wyss adds that Pioneer may contract with midwestern growers in the spring of 1999 to produce low-phytate grain for feeders in more environmentally sensitive areas.

Although Ontario does not legislate nutrient management planning, swine producers there are "keenly interested in the low-phytate trait," says Tim Welbanks, technical information manager, Pioneer Hi-Bred Ltd., Chatham, Ontario. "This is because we are surrounded by lakes and farms in an urban environment." No sacrifice. At Pioneer, corn hybrids featuring the low-phytate trait will undergo the samescrutiny as all of the company's products. "We will not sacrifice any trait," says Wyss. She says Pioneer has completed several third-party feeding trials with both swine and poultry that look encouraging. Preliminary tests indicate that Cargill's low-phytate corn lines perform agronomically as well as its conventional lines, says James Ulrich, grain quality traits specialist, Cargill Grain Division, Wayzata, MN. He adds that Cargill breeders are working to make sure that no agronomic traits are sacrificed. The trait has positive effects on rate of gain and feed efficiency, which will vary depending on the specific feed ration, says Ulrich. Because phytate binds other nutrients, such as zinc, magnesium and calcium, these nutrients will be more available in low-phytate corn, he says. Cargill will test low-phytate lines for yield this summer.

Dekalb Genetics will initially target areas where high phosphorus levels are an issue. Some states are taking a proactive environmental approach to phosphorus utilization in intensive livestock production areas, says John Hemingway, Dekalb product manager, corn quality and specialty traits. "We're looking at all of the traits in our pipeline and sizing up where they'll fit," he says.

Hemingway notes that Dekalb will test low-phytate corn for yield before releasing new products. "New traits must add value per acre. However, environmental issues in some locales may override what would otherwise be normal production decisions for the grower," he says.

Companies will need to show that yields of low-phytate hybrids are equal to or better than yields of elite hybrids on the market, says Tray Thomas, president, Context Consult-ing. This is because the trait has little impact on reducing the cost of dicalcium phosphate supplements, which do not cost much. Ulrich explains that producers who replace supplements with low-phytate corn in the future may save only $1/ton.

Fink adds that the trait's replacement value will depend on the growth stage of the animals being fed. "Different rations require different levels of dicalcium phosphate," he says.

Stacking traits. Fink notes that hybrids will be more valuable to feeders if the low-phytate trait is combined with other traits, such as high oil, high lysine and high methionine. Contract growers probably would not receive premiums for low-phytate grain alone, unless phosphorus management is mandated.

The price for low-phytate grain will depend mainly on the feeder's level of interest, suggests Fink. Some feeders may go directly to growers, asking if they can provide a steady supply of value-enhanced grain, and pay them on a per-acre basis, he says.

ExSeed's NutriDense LP corn has other desirable traits in addition to low-phytate. It has a minimum of 1% more oil and two to three more units of protein than No. 2 yellow corn. ExSeed reports that it contains about 28% more lysine, 16% more threonine, 25% more of both methionine and cystine, and 100% more tryptophan than conventional hybrids.

Dekalb is evaluating a wide array of nutritionally enhanced traits (such as high lysine and high tryptophan for swine, high methi-onine for poultry and modified oils) to stack with low phytate, says Hemingway. He adds that it is important to stack grain quality traits to increase the value of corn because more players (trait suppliers, growers, grain elevators and feeders) must capture value from output traits. With input traits, such as the Roundup Ready trait, the trait supplier and the grower are the main beneficiaries.

Selling the low-phytate trait. Kuebler says that NutriDense seed corn (without the low-phytate trait) costs $18.50 more per unit than conventional hybrids. NutriDense LP will carry the $18.50 premium plus a small royalty for the low-phytate trait.

ExSeed has not yet priced Yellow Dent LP. Kuebler says it will be priced much lower than NutriDense because it carries only the single low-phytate trait.Pioneer's Wyss says it makes sense to stack the low-phytate trait along with the elevated oil and amino acid traits. It would make inventory management less complex for seed suppliers and grain elevators, and end users would benefit from having several enhanced traits in one package.

Moreover, there already is an infrastructure in place for the contracting, identity preservation and delivery of high-oil corn through the value chain network of Optimum Quality Grains LLC (a joint venture between Pioneer and DuPont). Premium ranges have been established for high-oil corn. Companies could calculate premiums for other added traits using the high-oil corn pricing model.The low-phytate trait is most valuable to growers and feeders when stacked with other feed quality traits. However, if nutrient management planning is mandated, the low-phytate trait will become more valuable by itself. Fortunately, should that time come, low-phytate hybrids will be available.