103(3)_str39

 

ISSN 1392-3196 / e-ISSN 2335-8947
Zemdirbyste-Agriculture, vol. 103, No. 3 (2016), p. 305–310
DOI  10.13080/z-a.2016.103.039

Effect of the inoculant on the fermentation, microbial population and aerobic stability of whole plant maize ensiled in large tubes

Jonas JATKAUSKAS, Vilma VROTNIAKIENE

Abstract

This study evaluated the efficacy of the use of inoculant containing Lactobaillus buchnery in combination with homofermentative lactic acid bacteria strains Lactobacillus plantarum and Entrococcus faecium in improving characteristics of maize silage stored in a large tube. Maize plants were harvested at the dough stage of maturity, containing 339.6 g kg-1 dry matter (DM), chopped and ensiled in large tubes (1700–1800 kg each) after application of tap water (control) or inoculant suspension (inoculated) containing 1 × 108 cfu ml-1 of Lactobacillus plantarum, Entrococcus faecium and Lactobacillus buchneri (20:30:50). The final application rate of fresh forage was 1.0 × 105 cfu g-1 forage. The silos were stored for 156 days at outdoor temperature under farm conditions. After that the silos were opened and sampled, the chemical composition, the count of yeasts and moulds and aerobic stability were determined. Visible signs of mould growth on the surface of large tubes were assessed on day 0, 7, 14, 21, 28 and 35 after removing plastic cover from large tubes and scored using a scale from 0 to 5. The acetic acid concentration was higher in inoculated silages versus the control (20.3 vs 17.1 g kg-1 DM). The inoculated silages had a lower pH value and butyric acid concentration than the control, and a higher lactic-to-acetic acid ratio (1.95 vs 1.80). The inoculant treatment reduced DM losses (87 vs 74 g kg-1 DM). The counts of yeasts and moulds were lower in the inoculated silages when compared with the control silages, confirming the ability of this inoculum to enhance aerobic stability of maize silages in large tube silos. The surface area covered with moulds in the control large tubes was 4–5 times greater than that in the inoculated large tubes. Under laboratory conditions the aerobic deterioration of the inoculant treated silages was delayed by 72 hours (3 days) (P < 0.05) compared with the untreated silage. Treatment with inoculant significantly increased aerobic stability of large tube maize silages.

Key words: aerobic stability, inoculant, maize, molds, silage.

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