Detection and Phylogenetic Characterization of Virulence Genes of Escherichia coli Associated with Canine Urinary Tract Infections in India

Abstract

<strong>BACKGROUND: </strong><em>Escherichia coli </em>(<em>E.coli</em>) is one of the most common and important causative bacterium of urinary tract infections (UTIs) in both dogs and humans.<br /> <strong>OBJECTIVES: </strong>This study aimed to identify virulence genes and a phylogenetic group of E. coli isolated from the urine of dogs suffering from UTIs.<br /> <strong>METHODS: </strong><em>E. coli </em>were isolated from urine of dogs suffering from UTIs and tested for the presence of the virulence genes using conventional polymerase chain reaction (PCR) and sequencing method.<br /> On day 60 after immunization, half of the fish in each treatment was challenged intraperitoneally and the re- maining half of fish in the oral receiving bacterin groups were challenged by bath method with 1 LD50 and 1 LC50 of a <em>Y. ruckeri </em>local virulent isolate respectively.<br /> <strong>RESULTS: </strong>Out of a total of 103 samples, 25 were found to be positive for <em>E. coli</em>, of these 20 (80.0%) were identified as <em>aer</em>, 14(56.0%) as <em>pap</em>, 12(48.0%) as <em>sfa</em>, 8(32.0%) as <em>afa</em>, 5(20.0%) as <em>hly </em>and 5(20.0%) as <em>cnf1 </em>genes. None of the isolates carried <em>cnf2 </em>genes.<br /> <strong>CONCLUSIONS: </strong>The study demonstrated a high occurrence of virulence genes. The phylogenetic compar- isons of these gene sequences detected in uropathogenic <em>E. coli </em>isolated from dogs showed high similarity to those present in the urine of humans with urinary tract infection. Phylogenetic comparisons of the virulence genes revealed that <em>hly</em>, <em>sfa </em>, <em>cnf1 </em>and pap matched to group B2, afa to group A and aer to group B2 and D.