Effects of Lactobacillus buchneri on the nutritive value of sugarcane silage for finishing beef bulls

Lactobacillus buchneri 40788 and the fibrolytic enzymes β-glucanase and xylanase were applied to chopped sugarcane to study their effects on the nutritive value of silage. Sugarcane was mechanically harvested after 14 mo of growth and treated without (control) or with L. buchneri at a theoretical application rate of 5 × 10(4) cfu/g, 1 × 10(5) cfu/g, or 1 × 10(5) cfu/g plus enzymes. Forage was packed into farm-scale bag silos (40 t/silo) and stored for 92 d. Fifty-six bulls (32 Nellore and 24 Charolais × Nellore) were housed in 20 collective pens and fed diets comprising (dry matter [DM] basis) 458 g/kg sugarcane silage and 542 g/kg concentrates for an 84-d period. Treated silages had higher concentrations of acetic acid and lower concentrations of ethanol. Total mixed rations (TMR) containing inoculated silages exhibited significantly lower neutral detergent fiber (NDF) concentration and, consequently, higher in vitro DM digestibility (IVDMD). Thus, animals fed TMR containing treated silages spent less time chewing per day and per kilogram of DM intake (DMI), even at higher DMI levels. Nonetheless, the intake of NDF was similar across treatments (0.77 to 0.79 kg/100 kg BW) but markedly lower than the value reported for traditional forages. Average daily gain was significantly greater for animals fed TMR based on inoculated silages due to the higher DMI (14% on average) and the higher energy content of the diets, as indicated by the higher feed efficiency (12% on average). The dose of inoculants used and the addition of fibrolytic enzymes had no significant effects on silage parameters or animal performance. Therefore, inoculation of L. buchneri during sugarcane ensilage can alter the fermentation pattern by increasing acetic acid yield, reducing silage nutrient losses, and improving feed efficiency by bulls.