Ação combinada da torta de algodão e de inoculantes microbianos em silagens de sorgo forrageiro

Abstract

Sorghum is a tropical grass that has great adaptation to the Northeast region of Brazil and one of the most cultivated due to its high yield, mainly destined for silage, but have excess soluble carbohydrates that results in fermentative problems, in addition to a high moisture content. Thus, the objective of this work was to evaluate the effect of microbial inoculants and include cottonseed cake on the fermentative, microbiological profile and aerobic stability of the silage. The cultivar used was BRS Noire, harvested at dough stage, with a dry matter content of 27,85%. The cultivar used was BRS Ponta Negra, harvested at the pasty grain stage, with a dry matter content of 27.85%. The experimental design was randomized in a 2 x 4 factorial scheme (no cotton cake x no inoculant; silage inoculated with Lactobacillus plantarum; silage inoculated with Weissella cibaria and silage inoculated and combined with two microorganisms) with four replications. The silos were opened at 90 days after ensiling. There was an effect of the inclusion of pie and inoculants (P<0,05) for all variables analyzed. The inclusion of cotton cake promoted a buffering of the medium, maintaining the appropriate silage pH. The treatments favored the predominance of lactic bacteria. N-NH3 values indicate proteolysis, however, not compromising silage quality. The use of W. cibaria and the inclusion of cottonseed cake resulted in greater aerobic stability. Thus, it is concluded that the use of cottonseed cake as an additive in sorghum silage improves its fermentative and microbiological profile and increases aerobic stability, reducing losses, in addition to correcting protein deficit and low dry matter content. The use of W. cibaria, being a heterofermentative strain, is more efficient than the inoculation of L. plantarum.