Investigation of Escherichia coli O157 and Listeria monocytogenes presence and antibiotic susceptibility isolated from ruminant feces and feeds in Balikesir province

Abstract

In this study, which was conducted for the first time in Balıkesir, it was purposed to determine the existense, virulence factors and antibiotic susceptibility of Escherichia coli O157, which is zoonotic in ruminant feces and feed, and the pathogen Listeria monocytogenes, which causes diseases in humans and animals, and to use these results as epidemiological data in our province, region and country. Feces and animal feed samples were analyzed simultaneously for in order of E. coli O157 and L. Monocytogenes according to ISO 16654: 2001 / Amd 1: 2017 and ISO 11290-1. 38 E.coli O157 was isolated from a total of one hunderd stool samples. 18 L. monocytogenes were isolated from a total of one hunderd stool samples. 6 L. monocytogenes were isolated from 50 silage samples. Three of these isolates were isolated from faeces and silage samples taken from the same farm with L. monocytogenes isolates isolated from sheep feces. E. coli O157 could not be isolated from a total of 100 silage and feed samples. All L. monocytogenes isolates were susceptible to sulfamethoxazole / trimethoprim, tetracycline, streptomycin, meropenem and erythromycin. The highest resistance was detected against Sulbactam / ampicillin. 3 E. coli O157 isolates were found resistant to Gentamicin and 7 isolates to Tobramycin. 21 isolates were resistant to erythromycin, and 12 isolates were intermediate. According to PCR results of fliCH7, Stx1, Stx2, eaeA and EhlyA genes, EhlyA gene was found in 20 E. coli O157 isolates. Of these isolates, 4 were isolated from sheep feces and 16 from calf feces. The stx1 gene was found in a total of 5 E. coli O157 isolates, one from sheep feces and four from calf feces. EhlyA gene was also found in all isolates with stx1 gene. The stx2 gene was found in a total of 3 E. coli O157 isolates, one from sheep dung and two from calf dung. Intimin gene was found in 8 E. coli O157 isolates, two of which are sheep faeces and six calf faecal isolates. EhlyA gene was found in all isolates with intimin gene. In this study, enterohaemolysin is the predominant virulence factor among the isolates. Epidemiologically, silage was thought to be the main source of L. monocytogenes contamination, and recently, silage contamination continued in Balikesir.