title: Fermentation and microbial population dynamics during the ensiling of native grass and subsequent exposure to air.
abstract: To study the microbial population and fermentation dynamics of large needlegrass (LN) and Chinese leymus (CL) during ensiling and subsequent exposure to air, silages were sampled and analyzed using culture-based techniques and denaturing gradient gel electrophoresis (DGGE). A total of 112 lactic acid bacteria (LAB) strains were isolated and identified using the 16S rRNA sequencing method. Lactic acid was not detected in the first 20 days in LN silage and the pH decreased to 6.13 after 45 days of ensiling. The temperature of the LN silage increased after approximately 30 h of air exposure and the CL silage showed a slight temperature variation. Enterococcus spp. were mainly present in LN silage. The proportion of Lactobacillus brevis in CL silage increased after exposure to air. LN silage with a higher proportion of Enterococcus spp. and propionic acid concentration did not show higher fermentation quality or aerobic stability than CL silage, which had a higher concentration of acetic acid, butyric acid and increased proportion of L. brevis after exposure to air.
authors.affiliation: Institute of Grassland Science, College of Animal Science and Technology, China Agricultural University, Beijing, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan.
authors.forename: Baiyila
authors.initials: B
authors.lastname: Wu
authors.affiliation: Department of Animal Science, Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Nishino
authors.affiliation: Institute of Grassland Science, College of Animal Science and Technology, China Agricultural University, Beijing, China.
authors.forename: Xianguo
authors.initials: X
authors.lastname: Wang
authors.affiliation: Institute of Grassland Science, College of Animal Science and Technology, China Agricultural University, Beijing, China.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Yu
mesh_terms: D019342:Acetic Acid / Q000032:analysis; D000388:Air; D002087:Butyrates / Q000032:analysis; D016983:Enterococcus / Q000302:isolation & purification*; D005285:Fermentation; D052196:Levilactobacillus brevis / Q000302:isolation & purification*; D006109:Poaceae / Q000033:anatomy & histology* / Q000382:microbiology*; D011422:Propionates / Q000032:analysis; D012820:Silage / Q000032:analysis* / Q000382:microbiology*; D013696:Temperature; D013997:Time Factors
chemical_list: D002087:Butyrates; D011422:Propionates; C029658:propionic acid; D019342:Acetic Acid
keywords: aerobic stability; fermentation; microbial population dynamics; silage