Presence of sourdough lactic acid bacteria in commercial total mixed ration silage as revealed by denaturing gradient gel electrophoresis analysis
Article first published online: 31 JUL 2010
© 2010 The Authors. Journal compilation © 2010 The Society for Applied Microbiology
Letters in Applied Microbiology
Volume 51, Issue 4, pages 436–442, October 2010
How to Cite
Wang, C. and Nishino, N. (2010), Presence of sourdough lactic acid bacteria in commercial total mixed ration silage as revealed by denaturing gradient gel electrophoresis analysis. Letters in Applied Microbiology, 51: 436–442. doi: 10.1111/j.1472-765X.2010.02915.x
- Issue published online: 14 SEP 2010
- Article first published online: 31 JUL 2010
- 2010/1090: received 28 June 2010, revised 26 July 2010 and accepted 27 July 2010
- lactic acid bacteria;
- total mixed ration
Aims: To characterize the bacterial communities in commercial total mixed ration (TMR) silage, which is known to have a long bunk life after silo opening.
Methods and Results: Samples were collected from four factories that produce TMR silage according to their own recipes. Three factories were sampled three times at 1-month intervals during the summer to characterize the differences between factories; one factory was sampled 12 times, three samples each during the summer, autumn, winter and spring, to determine seasonal changes. Bacterial communities were determined by culture-independent denaturing gradient gel electrophoresis. All silages contained lactic acid as the predominant acid, and the contents appeared stable regardless of factories and product seasons. Acetic acid and 1-propanol contents were different between factories and indicated seasonal changes, with increases in warm seasons compared to cool seasons. Both differences and similarities existed among the bacterial communities from each factory and product season. Lactobacillus parabuchneri was found in the products from three of four factories. Various sourdough lactic acid bacteria (LAB) were identified in commercial TMR silage; Lactobacillus panis, Lactobacillus hammesii, Lactobacillus mindensis, Lactobacillus pontis, Lactobacillus frumenti and Lactobacillus farciminis were detected in many products. Moreover, changes owing to product season were distinctive, and Lact. pontis and Lact. frumenti became detectable in summer products.
Conclusion: Sourdough LAB are involved in the ensiling of commercial TMR silage. Silage bacterial communities vary more by season than by factory. The LAB species Lact. parabuchneri was detected in the TMR silage but may not be essential to the product’s long bunk life after silo opening.
Significance and Impact of the Study: Commercial TMR silage resembles sourdough with respect to bacterial communities and long shelf life. The roles of sourdough LAB in the ensiling process and aerobic stability are worth examining.