REMOVAL OF THE ALPHA-GALACTOSIDES OF SUCROSE FROM SOYBEAN-MEAL USING EITHER ETHANOL EXTRACTION OR EXOGENOUS ALPHA-GALACTOSIDASE AND BROILERPERFORMANCE

Two studies using broiler chicks and one using adult White Leghorn roo sters were conducted to determine the influence of stachyose and raffi nose (alpha-galactosides of sucrose) present in soybean meal (SBM) on the nutritional value of the meal. in Experiment 1, the addition of fo ur levels (0,.05, .10, or .20 g/kg) of a-galactosidase with and withou t 1 g/kg of invertase to a com-SBM diet had no effect on weight gain, feed efficiency, protein digestibility, or the digestible energy value of the feed when fed to broiler chicks. However, both enzymes decreas ed (P < .001) dietary AME(n). In Experiment 2, ethanol extraction and incubation of SBM with alpha-galactosidase decreased the concentration s of the cr-galactosides of sucrose in SBM from 6.59 to .81 and 1.43%, respectively. However, when broiler chicks were fed semi-purified die ts containing SBM, ethanol-extracted SBM, water-incubated SBM, or wate r plus alpha-galactosidase-incubated SBM, no improvements in weight ga in, feed efficiency, or apparent protein digestibility were observed. There was also no improvement in TME,when the above meals were precisi on fed to adult White Leghorn roosters (Experiment 3). These results i ndicate that the removal of up to approximately 90% of the cr-galactos ides of sucrose has no beneficial effect on the nutritional value of S BM for chickens.