Multilocus sequence typing of Enterococcus faecalis isolates demonstrating different lesion types in broiler breeders

Area of Science:

• Veterinary Microbiology
• Poultry Health
• Bacterial Pathogenesis

Background:

• Enterococcus faecalis is a significant bacterium in poultry, often associated with various disease conditions.
• Understanding the genetic diversity and specific strains of E. faecalis in broiler breeders is crucial for disease control.
• Previous studies have linked certain sequence types (STs) of E. faecalis to specific diseases in poultry, such as amyloid arthropathy.

Purpose of the Study:

• To characterize Enterococcus faecalis isolates from broiler breeders using multilocus sequence typing (MLST).
• To investigate potential correlations between specific STs and observed lesion types in broiler breeders.
• To compare STs from diseased birds with those from healthy carriers within the same population.

Main Methods:

• Multilocus sequence typing (MLST) was performed on 69 Enterococcus faecalis isolates from broiler breeders with lesions.
• Twenty isolates from healthy broiler breeders were included for comparative analysis.
• A total of 12 distinct sequence types (STs) were identified across all isolates.

Main Results:

• No direct correlation was found between specific STs and lesion types.
• Three STs (ST82, ST174, ST177) accounted for 81% of isolates from birds with lesions, suggesting a potential association with disease.
• ST174 was exclusively identified in affected birds, and ST82 showed diverse lesion associations and healthy carriers, differing from prior findings in layers.

Conclusions:

• Certain STs of Enterococcus faecalis, particularly ST82, ST174, and ST177, are frequently associated with disease lesions in broiler breeders.
• ST174 appears to be specifically linked to affected birds, warranting further investigation into its pathogenic potential.
• Phylogenetic analysis did not reveal distinct clusters for STs from healthy versus diseased birds, indicating complex host-pathogen interactions.