Document Detail

The ability of common mastitis-causing pathogens to survive an ensiling period.
MedLine Citation:
PMID:  21943753     Owner:  NLM     Status:  Publisher    
A forage-based study was conducted to examine the ability of enterococci, streptococci, and gram-negative bacteria to survive a 3-wk ensiling process. Harvested grass and corn forages were each divided into 3 treatment groups consisting of 2 commercially available silage inoculants and 1 negative control group. Within 24h of harvest, a uniform amount of forage was added to each of 18 vacuum-sealable freezer bags. Inoculants 1 and 2 were applied to each of 6 bags and the remaining 6 bags were not inoculated (negative control). All bags were sealed using an industry-grade vacuum sealer to create a pillow pack. At wk 1, 2, and 3 of the ensiling process, 6 bags were opened, 2 from each of the 3groups. Dry matter (DM), pH, and bacterial enumeration were determined on the forage before ensiling, as well as at wk 1, 2, and 3 of ensiling. The pH of grass and corn samples decreased to 5.2 and 4.1, respectively, by the end of the ensiling period. Inoculant 2 (7.3 log(10) cfu/g of DM) resulted in a greater enterococcal count in grass samples than did inoculant 1 (4.2 log(10) cfu/g of DM) at 3 wk of ensiling and both were greater than the negative control (1.2 log(10) cfu/g of DM). Counts of streptococci in grass samples at wk 3 were greater in inoculated samples (inoculant 1, 7.6 log(10) cfu/g of DM; inoculant 2, 7.0 log(10) cfu/g of DM) compared with the negative control (4.3 log(10) cfu/g of DM). Treatment differences were observed following 1 wk of ensiling in corn samples. Enterococcal counts on corn samples following the 3-wk ensiling were not significantly different between inoculant 1 (4.3 log(10) cfu/g of DM) and inoculant 2 (4.4 log(10) cfu/g of DM). However, counts in both inoculated groups were greater than in the negative control group (4.0 log(10) cfu/g of DM). No significant treatment differences were observed for streptococci counts at wk 3. Counts for gram-negative bacteria were not detectable by wk 3 of ensiling in either grass or corn samples. The addition of a silage inoculant led to greater counts of enterococci and streptococci in grass silage compared with the negative control at the end of a 3-wk ensiling period. The application of a silage inoculant led to increased enterococci counts, but not streptococci counts, in corn samples following the ensiling period. These data indicate that enterococci and streptococci are able to survive the pH decrease observed during ensiling.
C S Petersson-Wolfe; S Masiello; J S Hogan
Related Documents :
21192373 - β-trace protein as a diagnostic marker for perilymphatic fluid fistula: a prospective ...
7759663 - Excess cardiovascular and suicide mortality of affective disorders may be reduced by li...
8976723 - Risk factors for herpes simplex virus epithelial keratitis recurring during treatment o...
Publication Detail:
Type:  -    
Journal Detail:
Title:  Journal of dairy science     Volume:  94     ISSN:  1525-3198     ISO Abbreviation:  -     Publication Date:  2011 Oct 
Date Detail:
Created Date:  2011-9-27     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  2985126R     Medline TA:  J Dairy Sci     Country:  -    
Other Details:
Languages:  ENG     Pagination:  5027-5032     Citation Subset:  -    
Copyright Information:
Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Department of Dairy Science, Virginia Tech, Blacksburg 24061.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Temporal changes in plasma concentrations of hormones and metabolites in pasture-fed dairy cows duri...
Next Document:  Flow cytometric differential cell counts in milk for the evaluation of inflammatory reactions in cli...