AI Summary & Key Takeaways
AI InsightThe existence of different virulence factors found in this study supports the statement that calves are possible bearers of pathogens that are dangerous to public health.
📌 3 Key Takeaways
Abstract
Microorganisms have a primary role in the formation of calf diarrhea. Escherichia coli pose an environmental risk to young animals caused by fecal excretion. In this study, rectal swab samples (n= 133) were collected from calves with diarrhea aged from 1 day to 3 months, between August 2017 and August 2018. The samples were cultured on MacConkey agar, and then antimicrobial susceptibility and virulence genes for Escherichia coli isolates (n= 133) were investigated by disk diffusion method according to clinical and laboratory standards institute standards and multiplex polymerase chain reaction, respectively. The isolates were found to be highly resistant to oxytetracycline (78.9%), trimethoprim-sulfamethoxazole (69.2%), neomycin (60.9%), and erythromycin (58.6%). Besides, multidrug resistance was determined in 71.4% of isolates. Thirty-three of 133 (24.81%) isolates were positive for at least one virulence factor. The pathotypes of enterotoxigenic Escherichia coli (F5 and/or F41 fimbria and STa), enterohemorrhagic Escherichia coli (Stx and eae), enteropathogenic Escherichia coli (eae) and Shiga toxin-producing Escherichia coli (Stx-eae) were found in 51.5%, 6.1%, 15.2%, and 12.1%, respectively. However, the virulence properties were detected as; Stx1 (3.03%), Stx2 (9.09%), STa (21.21%), and eae (15.15%); the F41 and F5 were not detected. Also, the fifteen-point two percent of strains (5/33) were the hybrid type that carried both Stx (either Stx1 or Stx2) and enterotoxigenic Escherichia coli specific enterotoxin gene STa. The existence of different virulence factors found in this study supports the statement that calves are possible bearers of pathogens that are dangerous to public health.