The effect of Lactobacillus buchneri, alone or in combination with Lactobacillus plantarum, on the fermentation, aerobic stability, and ruminal degradability of low dry matter corn and sorghum silages was studied under laboratory conditions. The inoculants were applied at 1 x 10(6) cfu/g. Silages with no additives served as control. After treatment, the chopped forages were ensiled in 1.5-L anaerobic jars. Three jars per treatment were sampled on d 2, 4, 8, 15, and 90. After 90 d of storage, the silages were subjected to an aerobic stability test lasting 5 d, in which CO2 production, as well as chemical and microbiological parameters, was measured to determine the extent of aerobic deterioration. At the end of the ensiling period (d 90), the L. buchneri- and L. buchneri + L. plantarum-inoculated silages had significantly higher levels of acetic acid than the control and L. plantarum-inoculated silages. Therefore, yeast activity was impaired in the L. buchneri- and L. buchneri + L. plantarum-inoculated silages. As a result, L. buchneri, alone or in combination with L. plantarum, improved aerobic stability of the low dry matter corn and sorghum silages. The combination of L. buchneri and L. plantarum reduced ammonia N concentrations and fermentation losses in the silages compared with L. buchneri alone. However, L. buchneri, L. plantarum, and a combination of L. buchneri + L. plantarum did not effect in situ rumen dry matter, organic matters, or neutral detergent fiber degradability of the silages. The L. buchneri was very effective in protecting the low dry matter corn and sorghum silages exposed to air under laboratory conditions. The use of L. buchneri, alone or in combination with L. plantarum, as a silage inoculant can improve the aerobic stability of low dry matter corn and sorghum silages by inhibition of yeast activity.

The effect of 14 microbial inoculants on the fermentation and nutritive value of alfalfa silages was studied under laboratory conditions. The first cut (477 g of dry matter/kg) and second cut (393 g of dry matter/kg) of a second-year alfalfa stand were ensiled in 2 trials. In both trials alfalfa was harvested with standard field equipment. All inoculants were applied at 1.0 x 10(6) cfu/g of crop. Uninoculated silages served as controls. After inoculants were added, the chopped forages were ensiled in 1.0- and 0.5-L anaerobic glass jars, respectively, at a density of 500 g/L. Each trial had 15 treatments (uninoculated control and 14 inoculants), with 4 silos per treatment. Silos were stored for a minimum of 30 d at room temperature (approximately 22 degrees C). In first-cut silage, all inoculants but one reduced pH relative to the uninoculated control, and all but 2 of the homofermentative strains shifted fermentation toward lactic acid. In second-cut silage, the epiphytic lactic acid bacterial population was 2.7 x 10(7) cfu/g, and only commercial inoculants produced significant shifts in fermentation. Overall, microbial inoculants generally had a positive effect on alfalfa silage characteristics in terms of lower pH and shifting fermentation toward lactic acid with homofermentative lactic acid bacteria or toward acetic acid with heterofermentative lactic acid bacteria, Lactobacillus buchneri. These effects were stronger in the commercial products tested. In spite of the positive effects on silage fermentation, 48-h in vitro true DM digestibility was not improved by inoculation with lactic acid bacteria.

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Aims:To determine the effect of Lactobacillus buchneri, alone or in combination with homofermentative lactic acid bacteria (LAB), on the fermentation, aerobic stability and ruminal degradability of wheat, sorghum and maize silages. Methods and Results:The inoculants were applied at 1AE0 · 10 6 CFU g )1 . Silages with no additives served as control. Three jars per treatment were sampled on days 2, 4, 8, 15 and 60 after ensiling, for chemical and microbiological analysis. At the end of the ensiling period, the silages were subjected to an aerobic stability test. The L. buchneri-and L. buchneri + L. plantarum-inoculated silages had significantly higher levels of acetic acid than the control and L. plantarum-inoculated silages (P < 0AE05). Therefore, yeast activity was impaired in the L. buchneriand L. buchneri + L. plantarum-inoculated silages. As a result, L. buchneri, with or without L. plantarum, improved aerobic stability of the silages. The combination of L. buchneri and L. plantarum reduced pH, ammonia-N, and fermentation losses in the silages. However, L. buchneri, L. plantarum and L. buchneri + L. plantarum did not affect in situ dry matter, organic matters, and neutral detergent fibre degradability of the silages. Conclusions: The L. buchneri was very effective in protecting the wheat, sorghum and maize silages exposed to air under laboratory conditions. Significance and Impact of the Study: The use of L. buchneri, with or without homofermentative LAB, as a silage inoculant can improve the aerobic stability of silages by inhibition of yeast activity.

The aim of this work was to study the effects of temperature on the aerobic stability of wheat and corn silages. Three silage samples from each crop were taken from the faces of six different commercial bunker silos immediately after unloading them. The samples were exposed to air for 3 or 6 days at 10, 20, 30 or 40 degrees C. The most intensive deterioration occurred at 30 degrees C. Samples incubated at 30 degrees C had the highest yeast counts, most prolific CO(2) production and greatest increases in pH. Silage samples exposed to 10 or 40 degrees C remained stable. The duration of exposure had a significant effect on aerobic stability, especially at 30 degrees C. Temperature has a significant effect on silage aerobic stability. In a warm climate, special care should be taken during unloading of silage in order to prevent intensive aerobic deterioration.