Molecular detection and pyrG sequence analysis of Avibacterium paragallinarum using clinical samples of infraorbital exudates from layer chickens with infectious coryza symptoms in Indonesia

Background and Aim: Infectious coryza (IC) or snot, is caused by Avibacterium paragallinarum leads to upper respiratory disease in poultry. Various diagnostic methods are available, including isolation identification through bacterial culture biochemical tests. However, the subsequent of A. challenging because bacteria fastidious require specific growth factors. This study aimed detect clinical samples taken from exudate infraorbital sinus layer hens showing signs IC. Materials Methods: Samples were collected 10 with IC symptoms. Following DNA extraction, HPG-2 polymerase chain reaction (PCR) assays performed. The PCR amplicons underwent electrophoresis determine those correct target size (511 bp), these sequenced. resultant sequences analyzed using National Center for Biotechnology Information (NCBI) basic local alignment search tool. MEGA X was used bioinformatics analysis. Results: presence confirmed 4/10 samples. Bioinformatics analysis showed that amino acid sequence reference NCBI database grouped within same cluster. Furthermore, nucleotide 98.64%–100% similarity sequences. phylogenetic reconstruction partial pyrG 55 strains/isolates deposited GenBank four PCR-positive fell cluster, separate Pasteurella multocida, spp., Rodentibacter pneumotropicus clusters. Conclusion: infection molecularly (40%) amplicon detection. Clustering gene revealed positive Keywords: paragallinarum, bioinformatics, sequencesm, reaction.