Use of absorbants and inoculants to enhance the quality of corn silage

Khorvash, M., Colombatto, D., Beauchemin, K. A., Ghorbani, G. R. and Samei, A. 2006. Use of absorbants and inoculants to enhance the quality of corn silage. Can. J. Anim. Sci. 86: 97–107. This study examined whether inoculants and various absorbent materials could be used during ensiling to reduce effluent losses and improve nutritive value of corn silage. Two corn forages were harvested: conventional silage containing 29% dry matter (DM) and low DM silage containing 20% DM. Ninety-six mini-silos (10 cm × 1 m) were each prepared using 2.7 kg of chopped corn forage and one of the following compounds and add rates (fresh basis): no additive (control); 5, 10 or 15% ground barley; 5, 10 or 15% powdered whey; 5, 10 or 15% dried molasses; 1% bentonite; 1% zeolite; 0.5% zeolite plus 0.5% limestone; commercial inoculant containing Lactobacillus plantarum and Propionic bacteria sp. (BiotalTM, Lallemand Animal Nutrition, Rexdale, ON; 2 mg kg–1 fresh forage); commercial inoculant containing Lactobacillus plantarum and Pediococcus acidilactici (FeedtechTM, DeLaval, Tumba, Sweden; 24 mg kg–1 fresh forage ); and 1% zeolite plus Biotal inoculant. Effluent loss from the control low DM silage was high (74 mL kg–1; fresh basis), and was almost completely eliminated (P < 0.05) by adding barley (10 and 15%) or zeolite plus either limestone or bentonite during the ensiling process. Effluent loss from the control conventional silage was minimal (14 mL kg–1; fresh weight), and treatments caused no further reduction. For both silages, DM content increased (P < 0.05) with the use of barley (10 and 15%), whey (10 and 15%) or molasses. The pH of both silages increased (P < 0.05) using molasses or zeolite plus limestone. For both silages, acetic and lactic acid were increased (P < 0.05) with the addition of molasses, while zeolite plus limestone increased lactic acid content of conventional silage. For both silages, the addition of ground barley, whey, or Feedtech inoculant improved (P < 0.05) or tended (P < 0.10) to improve in vitro DM degradability (72 h) of corn silage, whereas degradability decreased (P < 0.05) or tended (P < 0.10) to decrease using molasses or zeolite plus limestone. High effluent losses that occur when corn forage is ensiled with a low DM content can be reduced by adding barley or zeolite plus either limestone or bentonite as an absorbant. However, of the compounds tested, only barley reduced effluent losses while improving nutritive value of the silage.