Effects of re‐ensiling on the fermentation quality and microbial community of napier grass (Pennisetum purpureum) silage

Abstract

BACKGROUND With the rapid development of animal husbandry, the silage trade has increased in frequency. The re‐ensiling of materials is often required before or after trading, resulting in the exposure of the silage to air before re‐sealing. To develop a re‐ensiling technique for silage, different silage exposure periods were simulated to check the possible effects on the fermentation quality and microbial community of silage. RESULTS Fresh and wilted napier grass (Pennisetum purpureum) were ensiled for 90 days, then exposed to air for 0, 6, 12, 24, 36 or 48 h, before being re‐ensiled. As a control, grass was directly ensiled for 180 days. Wilting increased the relative abundance of Klebsiella. The relative abundance of Paenibacillus in the unwilted silage was much higher than that in the wilted silage. Re‐ensiling increased the relative abundance of Lactobacillus, but decreased the relative abundances of Klebsiella, Bacillus, and Paenibacillus. In addition, Lactobacillus became the dominant bacteria in the re‐ensiled fresh and wilted silages. Re‐ensiling within 48 h of exposure did not affect the fermentation quality of the wilted silage, whereas that of the unwilted silage declined when exposed to air for over 24 h. CONCLUSION Re‐ensiling wilted napier grass silage within 48 h of aerobic exposure did not cause the fermentation quality to decline. The unwilted napier grass silage contained a higher relative abundance of Paenibacillus and significantly deteriorated when re‐ensiled after over 24 h of aerobic exposure. © 2021 Society of Chemical Industry

Gamma‐ray irradiation and microbiota transplantation to separate the effects of chemical and microbial diurnal variations on the fermentation characteristics and bacterial community of Napier grass silage

“…The most abundant phylum in MFM and PMFM was Proteobacteria, in agreement with Yuan et al 13 . and Yin et al 35 However, in AMFM, Firmicutes was found to be the most abundant phylum, reflecting the different abilities of Proteobacteria and Firmicutes to survive and multiply during the day and night. On the genus level, LAB genera represent only a small fraction of epiphytic microbiota.…”

The Potential of Pre-fermented Juice or Lactobacillus Inoculants to Improve the Fermentation Quality of Mixed Silage of Agro-Residue and Lucerne

“…A lower relative abundance of Erwinia in total mixed ration silage was associated with the improved silage quality ( Jiang et al, 2020 ), as this genus belongs to Enterobacteria , which can compete with LAB for substrate. Both Paenibacillus and Psychrobacillus may promote growth of less acid-tolerant spoilage microorganisms; they were detected in Napier grass silage and mixed corn and soybean silage ( Zeng et al, 2020 ; Yin et al, 2021 ). Furthermore, Carnobacterium apparently decreased fermentation quality of Italian ryegrass silage ( Yan et al, 2019 ).…”

Current approaches on the roles of lactic acid bacteria in crop silage

“…In addition, Weissella and Pantoea were the dominant genera in Napier grass in Malaysia (Hisham et al, 2022 ). Interestingly, Weissella and Lactobacilli were the dominant genera in Napier grass silages from different regions, and LAB inoculants or wilting treatments regulated the structure of microbial communities (Hisham et al, 2022 ; Yin et al, 2021 ; Zi et al, 2021 ).…”