Soybean meal from Roundup Ready® or conventional soybeans in diets for growing-finishing pigs.

World production of genetically modified (GM) soybeans is increasing; USDA’s national Agricultural Statistics Service has estimated that 68% of all soybeans grown in this country are genetically altered. Brazil’s State Seed Producers and Dealers Association (Apassal) indicated that Brazilian growers are planting unregistered GM seed from Argentina where 93% of the production is genetically modified. Apassal estimates that GM varieties will reach 45% of the soybean production in Brazil this year. Soybean growers seemed pleased with the effectiveness of using these new herbicide programs to reduce soybean losses due to weeds.

Several papers were presented at the American Society of Animal Science in July comparing the performance of GM grains with conventional grains. In research at the University of Kentucky, dehulled soybean meal was prepared from GM-herbicide tolerant soybeans containing the CP4 EPSPS protein (Roundup-Ready ®) and a near-isogenic conventional soybean source. The composition of the two meals was similar (DM: 90.3, 91.0%; CP: 51.5, 51.2%; NDF: 4.95, 4.85%; ADF: 3.50, 3.94%; lysine: 3.16, 3.09%; and methionine plus cystine: 1.47, 1.51%) for the conventional soybean meal and the soybean meal produced from Roundup Ready soybeans, respectively. The meals were evaluated in an experiment with growing-finishing pigs. The results indicated no significant differences between the meal sources for average daily gain, feed intake, feed required per gain, backfat, longissimus area, or calculated carcass lean. The CP4 EPSPS protein was not detected in the loin tissue of any of the pigs fed the soybean meal produced from Roundup-Ready soybeans. The authors concluded that the Roundup-Ready soybean meal is essentially equivalent in composition and nutritional value to soybean meal produced from conventional soybeans for growing-finishing pigs.

Cromwell, G.L. and co-workers. 2001. Soybean meal from Roundup Ready® or conventional soybeans in diets for growing-finishing pigs. J. Animal Sci. 79:Suppl.1 (abstract 1318).