Microbial and fermentation profiles, losses and chemical composition of silages of buffel grass harvested at different cutting heights

The present study evaluated the microbial population, fermentation profile, losses and dry matter recovery, and chemical composition of silages of buffel grass at different cutting heights. To evaluate the microbial fermentation dynamics, the treatments resulted from a 4 × 5 factorial combination consisting of 4 cutting heights and 5 fermentation periods, in a completely randomized design with three replications. The fermentation was evaluated at the end of 1, 3, 7, 15 and 30 days. The other characteristics of silages with 30 days were evaluated following a completely randomized design with four treatments, consisting of 4 cutting heights (30, 40, 50 and 60 cm), and five replications. Fermentation period and cutting height effects and interaction between both factors were observed on the populations of lactic acid bacteria (LAB), enterobacteria and molds and yeasts. The peak of development of LAB populations was observed on the seventh day of fermentation for the heights of 40 and 50 cm, with 8.25 and 8.30 log cfu/g, respectively. The pH values of silages ranged with different cutting heights, in which at the height of 50 cm the decrease was most pronounced. However, the pH values were similar between the cutting heights at the end of 30 days of fermentation. Quadratic relationship was observed between lactic acid concentrations and cutting heights. The crude protein content behaved linearly, initially showing 128.5 g/kg DM at 30 cm, decreasing as the cutting heights increased. The neutral detergent fiber and ether extract contents increased linearly with the cutting heights. Based on microbial populations, fermentation, losses and chemical composition, it is recommended to harvest buffel grass for silage from 50 cm on

Perfil fermentativo de silagens de cana-de-açúcar in natura ou queimada e tratadas ou não com Lactobacillus buchneri

Objetivou-se comparar as perdas, a dinâmica microbiológica e as alterações fermentativas e nutritivas de silagens de cana-de-açúcar in natura ou queimada e tratadas ou não com Lactobacillus buchneri durante o período de armazenamento. Os tratamentos foram cana-de-açúcar in natura ou tratada com L. buchneri e cana-de-açúcar queimada ou tratada com L. buchneri, avaliadas com 0, 1, 4, 7, 14, 28 e 56 dias de fermentação, em três repetições por tratamento. Apenas antes da ensilagem foi constatada diferença significativa na população de leveduras entre cana-de-açúcar in natura e queimada, cujos valores foram de 4,85 e 5,43 log ufc/g de forragem, respectivamente. No decorrer do tempo de fermentação, ocorreu redução da recuperação de matéria seca e as perdas se prolongaram até o dia 56. A concentração de etanol foi alta até o dia 28 e estável até o dia 56, sem diferença entre tratamentos. A digestibilidade verdadeira in vitro da matéria seca sofreu severa redução já no primeiro dia de armazenamento, chegando a reduzir cerca de 20 unidades percentuais aos 56 dias de armazenamento. Silagens de cana-de-açúcar queimada apresentam maiores perdas e alterações fermentativas e nutricionais que silagens de cana-de-açúcar in natura. O L. buchneri deve ser utilizado em silagens de cana-de-açúcar queimada, mas nas de cana-de-açúcar in natura seu uso é dispensável.The objective of this work was to compare losses, microbiological dynamics and nutritional and fermentative alterations in silages of fresh or burned sugar cane treated or not with Lactobacillus buchneri during storage period. Treatments were fresh sugar cane or treated with L. buchneri and sugar cane burned or treated with L. buchneri, evaluated with 0, 1, 4, 7, 14, 28 and 56 days of fermentation, in three replicates per treatment. Only before ensiling it was observed significant difference in the yeast population between fresh and burned sugar cane, whose values were 4.85 and 5.43 log ufc/g of forage, respectively. Over fermentation time, it occurred reduction of dry matter recovery and losses lasted until the 56th day. Ethanol concentration was high until day 28 and steady until day 56, with no difference among treatments. In vitro true dry matter digestibility was severely reduced in the first days of storage, reducing approximately 20 percentage units at 56 days of storage. Silage from burned sugar cane showed the greatest losses and changes on the fermentative and nutritional traits compared to fresh sugar cane silage. L. buchneri should be used on the burned sugar cane silage but for fresh sugar cane silage, its use is not necessary

Microbiological and chemical profile of sugar cane silage fermentation inoculated with wild strains of lactic acid bacteria

AbstractDuring sugar cane ensilage an intense growth of yeasts can result in high dry matter (DM) loss and reduction in the quality of the feed. The aim of this study was to evaluate the fermentation profile of sugar cane (Saccharum spp.) silage inoculated with new strains of lactic acid bacteria (LAB) screened for this forage silage. Fourteen wild LAB strains were evaluated, biochemically (API 50 CHL, BioMérieux) characterized, and identified by sequencing of 16S rDNA. The wild isolates were identified as Lactobacillus plantarum, Lactobacillus brevis, and Lactobacillus hilgardii. Different fermentation profiles were observed among strains of the same species. The silages inoculated with L. plantarum species showed the highest yeast population (5.97logCFU/g silage), ethanol concentration (137g kg/silage) and DM loss (20.6%) (P<0.01), therefore, they were not beneficial for sugar cane silage. The silages inoculated with L. brevis UFLA SIL17 and UFLA SIL24 and L. hilgardii UFLA SIL51 and UFLA SIL52 strains showed smaller DM loss (12.2%) and NDF-NDF content (573g/kg silage) (P<0.01). When compared with these inoculated silages, the silages inoculated with L. hilgardii UFLA SIL51 and UFLA SIL52 strains resulted in 57% and 94% more acetic acid and 1,2-propanediol respectively. Obligatory heterofermentative strains showed better silage quality. L. hilgardii (UFLA SIL51 and UFLA SIL52) strains show promise for use in sugar cane silage