An Assessment of the Viability of Lytic Phages and Their Potency against Multidrug Resistant <i>Escherichia coli</i> O177 Strains under Simulated Rumen Fermentation Conditions

• Main Authors: Peter Kotsoana Montso (Author), Caven Mguvane Mnisi (Author), Collins Njie Ateba (Author), Victor Mlambo (Author)
• Format: Book
• Published: MDPI AG, 2021-03-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

Preslaughter starvation and subacute ruminal acidosis in cattle are known to promote ruminal proliferation of atypical enteropathogenic <i>Escherichia coli</i> strains, thereby increasing the risk of meat and milk contamination. Using bacteriophages (henceforth called phages) to control these strains in the rumen is a potentially novel strategy. Therefore, this study evaluated the viability of phages and their efficacy in reducing <i>E. coli</i> O177 cells in a simulated ruminal fermentation system. Fourteen phage treatments were allocated to anaerobic serum bottles containing a grass hay substrate, buffered (pH 6.6-6.8) bovine rumen fluid, and <i>E. coli</i> O177 cells. The serum bottles were then incubated at 39 °C for 48 h. Phage titres quadratically increased with incubation time. Phage-induced reduction of <i>E. coli</i> O177 cell counts reached maximum values of 61.02-62.74% and 62.35-66.92% for single phages and phage cocktails, respectively. The highest <i>E. coli</i> O177 cell count reduction occurred in samples treated with vB_EcoM_366B (62.31%), vB_EcoM_3A1 (62.74%), vB_EcoMC3 (66.67%), vB_EcoMC4 (66.92%), and vB_EcoMC6 (66.42%) phages. In conclusion, lytic phages effectively reduced <i>E. coli</i> O177 cells under artificial rumen fermentation conditions, thus could be used as a biocontrol strategy in live cattle to reduce meat and milk contamination in abattoirs and milking parlours, respectively.

Item Description

10.3390/antibiotics10030265
2079-6382