Dissertação
Inoculação de silagem de capim-elefante com microrganismos do trato digestório de bovinos
Autor
Aniele de Cássia Rodrigues Veloso
Institución
Resumen
Elephant grass is used in the production of silage to supply animals when food
is scarce, but it is susceptible to deterioration by undesirable microorganisms
during fermentation. The objective of the work was to evaluate the inoculation of
Lactobacillus plantarum and of the fungal species Aspergillus terreus and
Trichoderma longibrachiatum from the bovine digestive tract in the ensiling of
elephant grass (Pennisetum purpureum cv. Cameroon). Two experiments were
carried out. In the first, two concentrations of L. plantarum in the silage of prewilted elephant grass and fermented in Falcon tube were evaluated. In the
second experiment it was evaluated the inoculation of the fungi A. terreus, T.
longibrachiatum and the mix of both fungi in the concentrations of 105 colony
forming units per gram (CFU / g) on the aerobic stability and bromatological and
microbiological composition of the fermented silage in PVC mini-silks. The
different inoculations and ways of preserving forage showed different results.
The inoculation of L. plantarum did not influence the losses of dry matter and
effluent, the pH and the microbiological community of the silage fermented in
Falcon tube, however it reduced the population of enterobacteria and caused
the absence of non-fermenting lactose bacteria. On the other hand, it was
verified that the inoculation of A. terreus and T. longibrachiatum positively
affected the levels of neutral detergent fiber and non-fibrous carbohydrates, the
aerobic stability of the silage and the community of microorganisms at the time
of opening and after 10 days aerobic exposure of silage. The MIX silage was
the most stable after aerobic exposure, but the control silage, A. terreus and T.
longibrachiatum showed lower losses of dry matter (P <0.05). The treatments
did not affect the levels of mineral matter, crude protein and ether layer (P >
0.05). Despite this, the silage inoculated with MIX presented a higher
concentration of fibers and a lower content of non-fibrous carbohydrates than
that inoculated with T. longibrachiatum. Only the final pH of the MIX silage
assumed a value above 4.2 considered for good fermentation. There was an
effect of the type of inoculation in the population of Diplococcus in the opening
of silage and rods, Lactobacillus and total lactic acid bacteria after 10 days of
aerobic exposure. In conclusion, the inclusion of A. terreus alone or in a mixture
with T. longibrachiatum improves the aerobic stability of the silage, but
increases the neutral detergent fiber content and reduces the non-fibrous
carbohydrate content.