Nutritive value of different varieties and morphological fractions of oats harvested at the soft dough stage

Chemical composition and in vitro organic matter digestibility (IVOMD) were measured in whole forage and morphological fractions of 20 varieties of oats (Avena sativa) harvested at the soft dough stage. Among the varieties, crude protein (CP) varied from 48 to 76 g kg−1 dry matter (DM), neutral detergent fibre (NDF) from 586 to 683 g kg−1 DM, acid detergent fibre (ADF) from 370 to 482 g kg−1 DM and lignin from 54 to 83 g kg−1 DM. The IVOMD of the whole forage ranged from 43 to 62%. Among the morphological fractions, leaf blades had the highest CP content and IVOMD, whereas the fibre constituents (NDF, ADF and lignin) were highest in the stems. The results revealed considerable variation in chemical composition and IVOMD among the oat varieties and morphological fractions. This implies that there are opportunities for improving forage production and quality from oats through appropriate exploitation of varietal differences. However, manipulation of management practices (such as choice of harvesting stage, use of mixed cropping with compatible legumes and fertiliser application) may still be needed for further improvement. Copyright © 2008 John Wiley & Sons, Ltd