Development and application of specific polymerase chain reaction assay targeting the gyrB gene for rapid detection of Riemerella anatipestifer

Abstract

A pair of PCR primers was designed and synthesized to amplify a gyrB gene sequence from Riemerella anatipestifer (RA). A fragment of 194 bp was detected in RA-positive isolates, whereas other isolates were negative, which confirmed the high specificity of the primers and PCR conditions. As little as 1.6 × 10(4) cfu/mL of cultural liquid was required by this method. We compared a 16S rRNA sequence-based PCR method and a Biolog bacterial identification system used in the detection and identification of suspicious isolates of RA in clinical tests. The results showed that the gyrB-based PCR was consistent with the results of the Biolog identification system and was more specific. By applying the gyrB-PCR to detect RA strains in 56 duck livers, a positive rate of 46% (26/56) was observed, whereas the positive rate of 85 throat swabs from clinically healthy ducks was 11%. Thus, this method could be used for the epidemiological investigation and preliminary isolate identification of RA.

SURVEILLANCE AND CHARACTERIZATION OF RIEMERELLA ANATIPESTIFER FROM WILD BIRDS IN SOUTH KOREA

“…Outbreaks of RA have caused economic losses on duck farms in many Asian countries (Loh et al 1992;Pathanasophon et al 2002;Wang et al 2012). In addition, there are seasonal migrations of wild birds that overwinter in these duck production areas, often mingling with farmed wild birds and ducks.…”

Chicken embryo lethality assay for determining the virulence ofRiemerella anatipestiferisolates

“…Chinese duck farms in 2012 showed high positive rates for R. anatipestifer, as 46% (26/56) of ducks had R. anatipestifer based on a clinical test and 11% (10/85) was observed in clinically healthy ducks in China (Wang et al, 2012). In 1996, 80% (39/49) of clinically healthy ducklings in Denmark had R. anatipestifer in their pharynx (Ryll et al, 2001).…”

SURVEY OF ARIEMERELLA ANATIPESTIFEROUTBREAK IN SOUTHERN TAIWAN DUCK FARMS

“…3 For this reason, some reports recommended PCR ampli¯cation of a partial region of the rpoB, gyrB, or 16S rRNA gene with subsequent sequencing for RA identi¯cation. 3,20,21 RAspeci¯c OmpA has also been proposed as an identi¯ca-tion target. 5,14 Our study performed PCR ampli¯cation for both 16S rRNA and OmpA genes, with 15 out of 27 isolates found to be positive for both genes.…”