Bacteriophage activity against and characterisation of avian pathogenic Escherichia coli isolated from colibacillosis cases in Uganda

Abstract

Avian Pathogenic Escherichia coli (APEC) cause colibacillosis leading to significant economic losses in the poultry industry. This laboratory-based study aimed at establishing stocks of avian pathogenic Escherichia coli lytic bacteriophages, for future development of cocktail products for colibacillosis management. The study determined the antibiotic susceptibility; phylogenetic categories, occurrence of selected serotypes and virulence genes among Escherichia coli stock isolates from chicken colibacillosis cases; and evaluated bacteriophage activity against the bacteria. Escherichia coli characterization was done through phenotypic and multiplex PCR methods. Bacteriophage isolation and preliminary characterization was achieved using the spot assay and overlay plating techniques. Fifty-six (56) isolates were phenotypically confirmed as E. coli and all exhibited resistance to at least one antimicrobial agent; while multi-drug resistance (at least three drugs) was encountered in 50 (89.3%) isolates. The APEC isolates mainly belonged to phylogroups A and D, representing 44.6% and 39.3%, respectively; whereas serotypes O1, O2 and O78 were not detected. Of the 56 isolates, 69.6% harbored at least one virulence gene, while 50% had at least four virulence genes; hence confirmed as APEC. Virulence genes, ompT and iutA were the most frequent in 33 (58.9%) and 32 (57.1%) isolates respectively; while iroN least occurred in 23 (41.1%) isolates. Seven lytic bacteriophages were isolated and their host range, at 1×108 PFU/ml, varied from 1.8% to 17.9% of the 56 APEC isolates, while the combined lytic spectrum was 25%. Phage stability was negatively affected by increasing temperatures with both UPEC04 and UPEC10 phages being undetectable at 70°C; whereas activity was detected between pH 2 and 12. The high occurrence of APEC isolates resistant against the commonly used antibiotics supports the need for alternative strategies of bacterial infections control in poultry. The low host range exhibited by the phages necessitates search for more candidates before in-depth phage characterization and application.

Antimicrobial resistance pattern of avian pathogenic Escherichia coli with detection of extended-spectrum β-lactamase-producing isolates in broilers in east Algeria

“…Similarly, Merati et al [23] in Tiaret Province showed that E. coli strains were entirely resistant to NA and OFX (100%). Regardless, these findings disagreed with a previous report in Uganda [24], which showed lower resistance to CIP and NA at 20.02% and 60.70%, respectively. The significant resistance to quinolones could be due to the excessive use of these compounds, as they have widespread availability in the Algerian market at a low cost.…”

“…Messai et al [5] and Ibrahim et al [3] found high resistance to SXT at 82% and 95.50%, respectively. Resistance to CN, C, and NIT was higher than in Benameur et al [27], Halfaoui et al [19], Boutaiba Benklaouz et al [12], and Kazibwe et al [24]. The administration of these antibiotics is forbidden in veterinary medicine in Algeria.…”

Genome Sequences of Bacteriophages UPEC01, UPEC03, UPEC06, and UPEC07 Infecting Avian Pathogenic Escherichia coli

“…The phage lysate obtained was plaque purified three times to produce a uniform phage stock. The isolated phages that could infect the APEC isolates from chickens that had died from colibacillosis were selected ( 4 ). Genomic DNA was extracted from the phages using 2% SDS and purified using a Qiagen Genomic-tip 100/G kit according to the manufacturer’s instructions.…”

Characterization and antimicrobial sensitivity of biofilm producing Avian Pathogenic Escherichia coli from broiler chickens and their environment in India.

“…100% among APEC isolates(Johnson et al 2008;De Oliveira et al 2015;Awawdeh 2018;Subedi et al 2018;Kazibwe et al 2020). This study along with others suggests that the ve genes used in the study are signi cantly associated to APEC isolates compared to non-APEC isolates(Johnson et al, 2008;Awawdeh 2018;Kazibwe et al 2020).…”

“…100% among APEC isolates(Johnson et al 2008;De Oliveira et al 2015;Awawdeh 2018;Subedi et al 2018;Kazibwe et al 2020). This study along with others suggests that the ve genes used in the study are signi cantly associated to APEC isolates compared to non-APEC isolates(Johnson et al, 2008;Awawdeh 2018;Kazibwe et al 2020). The high prevalence of these ve genes which encode for various virulence traits suggests the pathogenic nature of APEC and these virulence genes (VGs) may be involved at different stages of infection in poultry birds.…”