Investigating the presence and antibiotic susceptibilities of Escherichia coli O157 and Listeria monocytogenes in ruminant feces and feed in Balıkesir province

Abstract

The aim of this study is to determine the presence, virulence factors, and antibiotic susceptibilities of E. coli O157 and L. monocytogenes in ruminant feces and feed. This study was carried out for the first time in Balıkesir province. Feces, pellet feed, and silage samples were analyzed simultaneously for E. coli O157 and L. monocytogenes using feces of one gram and feed of twenty-five grams according to ISO 16654:2001/Amd 1:2017 and ISO 11290- 1, respectively. 38 (38%) E. coli O157 strains were isolated and identified from a total of 100 ruminant feces. A total of 3 (3%) E. coli O157:H7 strains were detected by PCR from one hundred ruminant fecal samples. In the study, resistance to antibiotics increased, especially in E. coli O157 isolates. In this study, enterohaemolysin was the predominant virulence factor among the E. coli isolates, and it was thought that it was important for pathogenesis. The Sxt1 gene was higher than the Stx2 gene. A total of 24 L. monocytogenes strains were isolated from a total of 100 ruminant fecal samples and 50 silage samples. Three of these strains were isolated from silage samples taken from the farms, where L. monocytogenes was isolated from sheep feces. As a result, poor quality silage could be an important source of infection for listeriosis in Balıkesir province. Epidemiologically, poor quality silage was thought to be one of the sources of listeriosis. It was thought that ruminant feces played an important role as a reservoir in the spread and transmission of E. coli O157. The antibiotic resistance status of E. coli O157 and L. monocytogenes isolates should be monitored with epidemiological studies.