Antônio Vinícius Iank Bueno

Effects of inoculation with homolactic bacteria on the conservation of wheat silage stored in bunker-silos

Abstract This study aimed to determine the effects of a homolactic inoculant on the nutritional value, fermentation pattern, aerobic stability and dry matter (DM) loss of wheat silage stored in farm-scale bunker silos. The experiment was carried out in a completely randomised design, whereas treatments were arranged in a 2 × 3 factorial scheme: wheat silage without inoculant (WS) or treated with a homolactic inoculants (Lactobacillus plantarum plus Pediococcus acidilactici at 1 × 105 cfu/g; WSI), evaluated in three silo layers (bottom, middle and top layers) of a bunker silo. The WS silage had higher levels of acetic, propionic and butyric acids and greater fermentative DM losses. However, the homolactic inoculant (WSI) worsened the aerobic stability. As previously expected, silage stored at the top layer had lower density and higher DM losses. In conclusion, the homolactic inoculant decreased the formation of volatile fatty acids and fermentative losses, but led to worse aerobic stability of wheat silages stored in bunker silos.

DRY MATTER OBTAINIMENT METHOD AND CHEMICAL COMPOSITION OF ROUGHAGES

Abstract It was aimed determinate the influence of drying methods on nutritional composition of different roughages. The experimental material were four grass species (Urochloa brizantha cv. Marandu, Urochloa brizantha cv. MG4, Cynodon dactylon cv. Coastcross e Panicum maximum cv. Aries), one forage legume (Stylosanthes cv. Campo Grande) and two silages (Zea mays e Triticum aestivum cv. BRS Umbu). The drying methods were based on use of forced air oven or microwave oven. The experimental design were a 2 x 8 factorial arrangement (2 drying methods and 8 roughages) with 4 repetitions. There was no effect of drying method on roughages dry matter content. Microwave oven drying increased neutral detergent fiber. There was an interaction between drying method and evaluated roughage. Increased contents of crude protein (estilosante), neutral detergent insoluble nitrogen (Coastcross, MG4, Marandu e estilosante) and ether extract (MG4, estilosante e Aries) were observed when roughages were dried using microwave oven. The microwave oven usage is an alternative to obtain the dry matter content of roughages; however this technic may affect the sample composition.

Parâmetros nutricionais e estabilidade aeróbia de silagens de cereais de inverno submetidas a diferentes regimes de corte no estádio vegetativo

ABSTRACT The use of cutting regimes in vegetative stage for winter cereals is interesting when it seeks to intensify the forage production for ruminants. However, it is necessary to ascertain the impact of this management on the characteristics of the resulting silage. Thus, the aim of the experiment was to evaluate the nutritional quality and aerobic stability of winter cereal silages submitted to cutting regimes in vegetative stage, before ensiling. The materials used were: wheat (Triticum aestivum cv. BRS Gralha Azul); barley (Hordeum vulgare cv. BRS Brau); white oat (Avena sativa cv. URS Guara); black oat (Avena strigosa cv. Embrapa 139) and triticale (X Triticosecale cv IPR 11); associated with three management strategies: without previous cuts (Only silage), one cut and two cuts in vegetative and posterior silage making. Barley owned low values of ADF (311.7 and 375.3g kg de DM -1 ) and high TDN (569.2 and 533.4g kg de DM -1 ) for one and two-cut system, respectively. For aerobic stability, materials were quite stable after opening the silos, with the exception of black and white oat in management without cuts. Triticale and barley silage had the highest nutritional stability with the increase in the number of cuts. Keywords: barley, protein, triticale, wheat