Effect of Anti-yeast on Sugarcane Silage Gas Production

Although sugarcane produces a large amount of energy per hectare, its ensiled storage leads to losses, which makes it one of the most expensive options for animal feeding. These losses occur due to fermentation of sugars and organic acids by yeasts, producing alcohol and gas. Inoculants containing Lactobacillus buchneri increase acetic acid production, which has effect against yeast. In this study, we produced egg yolk antibodies (IgY) against yeasts that ferment lactate (Candida glabrata, Pichia kudriavzevii, and Pichia manshurica) and sugar (Saccharomyces cerevisiae, Torulospora delbrueckii, Schizosaccharomyces pombe and Debaryomyces etchellsii) isolated in sugarcane silage. Shortly before ensiling, doses of 0, 175, 350, and 700 g/t IgY, and Lactobacillus buchneri were applied to chopped forage. Gas losses were calculated using experimental silos in triplicate, according to the equation: G = (PCf - PCa)/(MFf) × 100, in which: G = gas losses (kg/t); PCf = weight of full silo (equipped with a Bunsen valve to allow gas outflow) at sealing (kg); PCa = weight of full bucket at opening (kg); MFf = forage mass at sealing (kg). The data were analyzed as a completely randomized design and submitted to analysis of variance and regression using the SAS (SAS, 1998), which was chosen because of the significance of the regression parameters, tested by Tukey’s test (P < 0.05) and the values of the coefficients of determination. Thirty days after sealing the L. buchneri inoculant and doses of 350 and 700 g/t IgY promoted less gas losses than control that had no any product (12.74; 15.59 and 15.28 versus 27.74, respectively, P < 0.05) and the L. buchneri did not differ from IgY doses. The gas losses decreased quadratically with the anti-yeast addition, estimating maximum of 530 g/t fresh forage. We conclude that anti-yeast use reduces gas production during fermentation. With continuity of this research, we may obtain a roughage with higher nutritional value, as its mode of action in yeast control does not involve consumption of sugars or organic acids.