Effect of lactic acid bacteria on the ensiling characteristics and in vitro ruminal fermentation parameters of alfalfa silage

The objective of this study was to evaluate the effects of lactic acid bacteria (LAB) inoculants on fermentation quality and subsequent in vitro gas production, ruminal fermentation parameters, cellulolytic bacteria and their activities of alfalfa silage. Primary growth of alfalfa (Medicago sativa L...

Full description

Bibliographic Details
Main Authors: Wenjie Huo, Xinyu Wang, Zhixia Wei, Haixuan Zhang, Qiang Liu, Shuanlin Zhang, Cong Wang, Lei Chen, Qingfang Xu, Gang Guo
Format: Article
Language:English
Published: Taylor & Francis Group 2021-01-01
Series:Italian Journal of Animal Science
Subjects:
Online Access:http://dx.doi.org/10.1080/1828051X.2021.1906167
Description
Summary:The objective of this study was to evaluate the effects of lactic acid bacteria (LAB) inoculants on fermentation quality and subsequent in vitro gas production, ruminal fermentation parameters, cellulolytic bacteria and their activities of alfalfa silage. Primary growth of alfalfa (Medicago sativa L.) was harvested at 50% flowering stage, inoculated without (control) or with Lactobacillus plantarum, Enterococcus mundtii and Enterococcus faecalis at 1.0 × 106 cfu/g of fresh weight (FW) in quadruplicate laboratory silos for 45 d. The silage inoculated with LAB were well preserved, indicated by the lower (p < .05) pH and ammonia-N content and the higher (p < .05) dry matter (DM), organic matter (OM), crude protein and lactic acid contents than the control silage. In vitro asymptotic gas and total volatile fatty acids production were higher in all LAB-treated silages (p < .05). All inoculants increased carboxymethyl-cellulase and β-glycosidase activities, and obtained higher DM and neutral detergent fibre degradability (p < .05) except E. mundtii. Similarly, L. plantarum and E. faecalis inoculants had higher (p < .05) Ruminococcus albus and Fibrobacter succinogenes relative proportions than the control. However, L. plantarum inoculants had lower (p < .05) percentage of methane (CH4) in 72 h gas production than the control and E. faecalis inoculants. These results suggested that L. plantarum were more effective in enhancing alfalfa silage utilisation by promoting forage digestibility and reducing ruminal CH4 emission than E. mundtii and E. faecalis.HIGHLIGHTS Lactic acid bacteria (LAB) inoculants improved alfalfa silage quality. Silage treated with Lactobacillus plantarum or Enterococcus mundtii increased gas production but reduced the percentage of methane in vitro. L. plantarum and Enterococcus faecalis promoted neutral detergent fibre digestibility by increased rumen cellulolytic bacteria proportion and cellulase activity.
ISSN:1594-4077
1828-051X