AN INVESTIGATION INTO THE VARIABILITY OF EXTRACT VISCOSITY OF WHEAT -RELATIONSHIP WITH THE CONTENT OF NON-STARCH-POLYSACCHARIDE FRACTIONS AND METABOLIZABLE ENERGY FOR BROILER-CHICKENS

The vitro extract-viscosity and the content of non-starch-polysacchari des were investigated in 34 defined wheat varieties grown at 5 locatio ns each. Both, wheat genotype as well as growing location clearly infl uenced the viscosity of soluble extract from wheat. Furthermore, the c ontent of non-starch-polysaccharides (soluble/total) and pentosans (so luble/total) were determined in 13 wheat varieties each grown at two l ocations. Soluble pentosan contents were highly positively correlated with extract viscosity of wheat at the locations Hayn (r = 0.86) and B iendorf (r = 0.90). The classical apparent metabolisable energy of 5 w heat samples having different extract viscosities was assessed. The AM E(N) values ranged from 14.0 to 14.6 MJ/kg DM and were significant neg atively correlated to content of soluble arabinoxylans (r = 0.67) and to the extract viscosity (r = 0.83). Furthermore, the viscosity of jej unal (4.0 to 22.8 mPas) and ileal (13.1 to 78.0 mPas) digesta exhibite d a clear relationship with soluble pentosan contents and extract visc osity. Under the conditions applied in this study the technique of ext ract viscosity measurement can predict the AME.