Effects of an indigenous and a commercial Lactobacillus buchneri strain on quality of sugar cane silage C. L. S. A ´ vila*, J. C. Pinto*, H. C. P. Figueiredo† and R. F. Schwan‡ Departments of *Animal Science, †Veterinary Science and ‡Biology, Federal University of Lavras, Lavras, MG, Brazil Abstract The aim was to evaluate the effects of adding a novel Lactobacillus buchneri strain and a commercial inoculant on the fermentation and aerobic stability of sugar cane silages (Saccharum spp.). In the first experiment samples were collected from sugar cane silage at 5, 20, 40 and 80 d after ensilage in experimental silos and microor- ganisms belonging to the Lactobacillus genus were isolated and identified, with a wild strain of L. buchneri, UFLA SIL 72, being selected as an inoculant. In the second experiment sugar cane was inoculated with either the novel bacteria or a commercial inoculant at the moment of ensiling and compared with a control silage prepared without an inoculant. Experimental silos were opened at 0, 3, 10, 30, 60 and 90 d of ensilage and their chemical composition measured. The silages opened after 90 d were also assessed for aerobic stability. The addition of L. buchneri resulted in a higher concentration of acetic acid and reduced populations of yeasts in silage compared to the other silage treatments, and a lower ethanol concentration in the silage. The novel L. buchneri isolate and the commercial inoculant also improved aerobic stability of the sugar cane silages. It was concluded that the addition of the novel inoculants L. buchneri UFLA SIL 72 to sugar cane silage can be recommended. Keywords: aerobic stability, Lactobacillus buchneri, mic- robiota, sugar cane silage Introduction Sugar cane has several characteristics that make it suitable for use in ruminant livestock, such as its ease of cultivation and high efficiency in converting solar energy to biomass, which results in a high herbage production (25–40 t DM ha )1 ). The cultivation of sugar cane also has a low production cost per ton of dry matter (DM). The nutritive value of sugar cane is maintained for up to 6 months after maturation, and the ideal harvesting phase coincides with a period of shortage of feed during the dry season of the year. Finally, sugar cane has an abundance of sugars that are highly digestible and that can account for 230 g kg )1 of the DM (Pedroso et al., 2005). Sugar cane has some favourable aspects for the process of silage production. It has a DM content of 250–300 g kg )1 , a high concentration of soluble carbo- hydrates and a buffering capacity that permits the rapid decrease to a pH of 3Æ5 (Freitas et al., 2006). Sugar cane silage, however, is susceptible to a high degree of alcohol fermentation by yeasts, leading to high rates of DM loss (Kung and Stanley, 1982). The loss of DM during sugar cane fermentation results in an accumu- lation of cell-wall components and reduced DM digest- ibility. Furthermore, the silage has high residual carbohydrates and lactic acid concentrations. These compounds are substrates for silage-deteriorating microorganisms after the silos are opened (McDonald et al., 1991). During silage production and use, both the aerobic and the anaerobic activities of yeasts are considered undesirable. Under anaerobic conditions, yeasts fer- ment sugars to ethanol and carbon dioxide. The ethanol produced decreases the quantity of the sugar available for the lactic-acid bacteria (LAB). Ethanol is also related to the organoleptic quality of milk (Gordon and Morgan, 1972; Randby et al., 1999), changes in ruminal fermentation with increases in ruminal acetate and caproate concentrations (Chalupa Correspondence to: R. F. Schwan, Departamento de Biologia, Universidade Federal de Lavras, 37Æ200-000 Lavras, MG, Brazil. E-mail: rschwan@ufla.br Received 3 July 2009; revised 16 July 2009 Ó 2009 Blackwell Publishing Ltd. Grass and Forage Science, 64, 384–394 doi: 10.1111/j.1365-2494.2009.00703.x 384