Soybean Isoflavones

Performance and carcass quality of pigs fed either soybean meal or soy protein concentrate were compared in a feeding study. The diets were formulated to contain equal levels of energy, protein and amino acids. The experimental variable was the isoflavone content (daidzein plus genistein) of the protein sources (soybean meal, 782 ug/g; soy protein concentrate 125 ug/g). Results indicated absorption of isoflavones since circulating blood plasma levels of genistein, daidzein and equol reflected dietary levels; however, treatment had no affect on performance (gain, feed intake, feed/gain) or carcass quality (percent of cuts or lean, meat quality).

Kuhn, Gerda and co-workers. 2004. Different isoflavone content in soy-based diets are without influence on growth performance and carcass quality in pigs. Poster #T56, p177 of the 2004 Joint Annual Meeting abstracts.