Acta Scientiarum: Agronomy (Apr 2009)
Efeitos da aeração sobre as características da silagem de cana-deaçúcar = Effects of aeration on characteristics of sugarcane silage
Abstract
No presente estudo, objetivou-se avaliar os efeitos do tempo de aeração sobre as características nutricionais e fermentativas da silagem de cana-de-açúcar. Utilizou-se o delineamento inteiramente casualizado com três tratamentos e quatro repetições. A cana-deaçúcarrecém-picada foi exposta à aeração por 0, 4 ou 8 horas, sendo ensilada somente após cada tempo de espera. Após a exposição, o material foi ensilado em 12 silos experimentais confeccionados de baldes plásticos. A abertura dos silos ocorreu 85 dias após a ensilagem. Foram determinados os teores dos ácidos orgânicos e a composição químico-bromatológica das silagens. Foi observado desvio da linearidade (p This trial aimed at evaluating the deleterious effects of aeration time on nutritive value and other fermentative characteristics of sugarcane silage. A completely randomized design was usedwith three treatments and four repetitions per treatment. Fresh chopped sugarcane was exposed to aeration for 0, 4 or 8 hours, and ensiled soon after. After exposure, the material was ensiled in 12 laboratory silos (plastic buckets). Silos were opened 85 days after ensiling, when organic acids contents and chemical composition of silages were determined. Deviation of linearity (p < 0.05) was observed for aeration time on dry matter. A positive linear effect was observed (p < 0.05) on ADF, NDF and soluble carbohydrates content, but negative for ammoniacal nitrogen content and in vitro digestibility of dry matter. For organic acids content, deviation of linearity was observed on acetic acid, with the lowest content(1.5% of DM) observed after 8 hours of aeration, and a negative linear effect was observed for lactic and butyric acids, as well as for pH values. There were no effects on ethanol concentration, which remained very high (22% of DM), regardless of aeration time. Aerobicstability of silage worsened with the increase in aeration time.