Low Phytate Soybeans

A study was conducted to compare the effect of feeding soybean meal produced from low-phytate soybeans on performance and phosphorus excretions of growing swine. Ninety-six crossbred barrows weighing about 18 kg were allocated to twenty-four pens. The four treatments were: 1) the control diet (SBM without supplemental phytate; 2) SBM plus 500 phytase units/kg; 3) low-phytate SBM; and 4) low phytate SBM plus phytase. The diets were formulated to be isocaloric and to contain similar levels of available lysine and non-phytate phosphorus. Results indicated that there were no significant (P>0.05) treatment effects on average daily gain, average daily feed intake, feed conversion or digestibility of dry matter or organic matter. Adding phytase, or genetically reducing the phytate in the soybean, significantly reduced (P>0.01) total phosphorus and water-soluble phosphorus in the four treatments. Phytase additions increased the proportion of total phosphorus that was excreted as water-soluble phosphorus from 55 percent to 59 percent. These results indicate that phosphorus excretion can be reduced in growing pigs by feeding phytase and/or SBM containing reduced phytate phosphorus levels.

Power, W.J. and co-workers. 2006. Total and water-soluble phosphorus excretion from swine fed low-phytate soybeans. J. Animal Sci. 84(7): 1907-1915.