Carbohydrates fractioning of late crop corn silages harvested at different cutting height

摘要

> face="Verdana, Arial, Helvetica, sans-serif" size="2">The objective was to verify if there are changes in the carbohydrates composition of late crop corn silages harvested at 20, 45, 70 and 95cm of cutting height (CH). The research was conducted in a randomized entirely design with four replications (mini-silos) per treatment. The dry matter content increased linearly DM=27.25+0.06928*CH (R2=0.82 and P0.01) with the CH elevation due to the larger grain proportion in the ensiled mass. The neutral detergent fiber corrected for ashes and protein (NDFap) and lignin (ADL) values lowered with the CH elevation, NDFap=43.75–0.08411*CH (R2=0.47 and P0.01) and ADL=6.983–0.03156*CH (R2=0.49 and P0.01), respectively. The carbohydrates B1=27.16+0.1239*CH (R2=0.66 and P0.01) fraction and the non-fiber carbohydrates NFC=41.57+0.07861*CH (R2=0.54 and P0.01) increased linearly with the CH elevation. The late corn cropping in the south region of Brazil lead to high quality silages, with high starch and low neutral detergent fiber values. The CH elevation in the corn plant changes the carbohydrates distribution, with higher starch and lower neutral detergent fiber and lignin values in the silage.