ISOLATION AND MOLECULAR IDENTIFICATION OF AVIBACTERIUM PARAGALLINARUM IN LAYERS BY USING SYBR GREEN REAL TIME PCR

Infectious coryza is an infectious disease, caused by Avibacterium paragallinarum, causing economic losses tocommercial poultry Industry. The samples were collected from 6 commercial Infectious Coryza suspected layer farmsincludes, nasal swabs(119), ocular swabs(119) and tracheal swabs(119) were pooled farm wise and organ wise. Onoselective media the organism was produced satellite colonies after incubation of 48 hours at 37 c under anaerobicconditions. The organisms were showed positive test for sugar fermentation tests, negative for catalase test,Indole testand H2S production test. Further molecular confirmation was done by SYBR Green real time PCR by targeting the HPG2gene. In this study the Ct value below 35 was consider as positive cutoff for Avibacterium paragallinarum. All sampleswere screened by targeting HPG2 gene and found 100 percent positive for Avibacterium paragallinarum. To control theeconomic losses associated with the Infectious coryza, an early ,accurate and rapid diagnosis is essential. So the SYBRGreen real time PCR is a rapid and highly sensitive technique which can substitute conventional methods. Theantibiogram pattern revealed that the isolated pathogens were showed the sensitivity to enrofloxacin,ceftriaxone andamikacin. The diagnosis can be done by isolation of the pathogen on selective media and identification by biochemicaltests, but less sensitive and time consuming. So the molecular detection based PCR tests are the most advanced, amongthe PCR tests, SYBR Green real time PCR test is the rapid, accurate and most sensitive test in detection of pathogens.Hence the present study was aimed that isolation and molecular detection of Avibacterium paragallinarum incommercial layers by using SYBR Green real time PCR by targeting HPG2 gene.