Isolation and polymerase chain reaction-based identification of Riemerella anatipestifer from ducks in Kerala, India

Abstract

The aim was to isolate and characterize Riemerella anatipestifer organisms from disease outbreaks in ducks in Kerala.Materials and Methods: Ducklings, suspected of Riemerella infection, were sacrificed and subjected to post-mortem examination. Heart blood smears and impression smears from liver and spleen were examined for the presence of pathogenic organisms. Heart blood, lung, liver, and spleen collected aseptically from the birds were subjected to isolation trials in brain heart infusion agar and 10% bovine blood agar. The isolates were characterized based on morphology, cultural characteristics and biochemical tests, and their identity were confirmed by polymerase chain reaction (PCR) and the PCR amplified DNA was sequenced. The antibiotic sensitivity testing of the isolates were carried out using six antibiotics viz ciprofloxacin, chloramphenicol, enrofloxacin, amoxycillin, cotrimoxazole, and gentamicin.Results: Colonies suggestive of Riemerella organisms could be isolated on blood agar. Biochemical characterization and PCR confirmed the identity of isolates as R. anatipestifer. The nucleotide sequence of the PCR product showed 99% homology to the R. anatipestifer sequences in the NCBI. The antibiogram revealed that the organisms were sensitive to ciprofloxacin, enrofloxacin, and gentamicin. Conclusion:The present study suggests that the PCR assay can facilitate fast and proper identification of R. anatipestifer infection in ducks. The assay can also differentiate between R. anatipestifer and Pasteurella multocida and can replace the traditional methods of differentiation which are cumbersome and time-consuming.

Comparison of Polymerase Chain Reaction- Restriction Fragment Length Polymorphism (PCR-RFLP) and Repetitive Sequence-PCR (REP-PCR) for Differentiation of Riemerella anatipestifer Isolates

“…A species-specific PCR assay developed by Kardos et al, (2007), revealed the presence of 546 bp PCR product. Similar results were observed by Soman et al, (2014) andShancy, (2015) to confirm the RA isolates. This PCR assay, could easily replace the traditional method of identification to identify the isolate from clinical samples, as it was highly sensitive and specific.…”

Molecular Characterization, Virulence and Antimicrobial Susceptibility Testing of <i>Riemerella anatipestifer</i> Isolated from Ducklings

“…On the other hand, R. anatipestifer isolates were highly sensitive to amikacin, imipenem and rifampin. These results nearly agreed with Zhong et al (2009) ; Chang et al (2019) ; and Soman et al (2014) . The multiple drug resistances were found in all R. anatipestifer isolates (Table 2) .…”

Molecular detection and antibiogram profile of Riemerella anatipestifer in duck farming areas of Bangladesh

“…For more accurate diagnosis conventionally biochemical tests including Indole production, Methyl-red test (MR), Voges-Proskauer (VP) test, H 2 S production, and Oxidase and Catalase test, sugar fermentation (glucose, lactose, maltose, mannitol, dextrose, sucrose) test have been used and produced the similar results mentioned in (Sarker et al 2017); fermentation of dextrose, lactose, maltose, mannitol, glucose, sucrose, MR test positive, VP and Indole negative, and Catalase positive. Similarly, oxidase test positive and H 2 S negative mentioned by (Surya et al 2016; Shancy et al2018).The PCR is considered as gold standard, regarding speci city, sensitivity, and reliability for detecting microbial causal agents of diseases(Soman et al 2014). In this study, PCR was performed targeting the Riemerella species speci c gene designed by(Kardos et al 2007) and gyrB gene primarily.…”