Effect of particle size and cutting height of corn on the dynamics of the silage fermentation process and feed-out period

[摘要] The trial aimed to evaluate the effect of particle size (small: from 0.2 to 0.6 cm or large: from 1.0 to 2.0 cm) and cutting height (low cut: 15 cm or high cut: 39 cm) of the corn plant on the dynamics of the silage fermentation process and feed-out period. The treatments were: T1 - small particle size with low cutting height; T2 - large particle size with low cutting height; T3 - small particle size with high cutting height; and T4 - large particle size with high cutting height. A complete randomized blocks design with a factorial arrangement (2 x 2 x 4) in a split-plot was used, with three replications. Factors evaluated were particle size (2), cutting height (2), and feed out evaluation periods (4). Small particle size improved compaction density and reduced temperature gradient between silage mass and environment and pH value of silage during feed-out. Higher deterioration of corn silage occurred at the superior silo stratum, due to temperature elevation and higher pH index and ammoniacal nitrogen compared to inferior stratum.

[学科分类] 兽医学

[关键词] ammoniacal nitrogen;packing level;pH;silage temperature     IntroduçãoNo Brasil poucas pesquisas foram realizadas visando à quantificação das perdas absolutas na ensilagem e;na maior parte;esses resultados não representam a real situação do produtor;pois a maioria é conduzida utilizando-se de silos laboratoriais em condições que não refletem a realidade do processo