Pheno- and genotypic investigation of Ornithobacterium rhinotracheale isolates of commercial poultry samples sent to Razi institute, Iran

The aim of the present study was the pheno- and genotypic investigation of Ornithobacterium rhinotracheale (ORT) isolates of commercial poultry in different areas of Iran based on conventional bacterial method and polymerase chain reaction (PCR) technique. For this purpose, 25 bacterial samples were selected from the microbial bank of the Avian Diseases Research and Diagnosis Department of Razi Institute. The cultural and biochemical investigations were identified all of the samples as ORT isolates. The isolates were also confirmed by PCR based on a 784-bp amplified fragment related to the estimated length. According to the results of determination of the haemagglutination pattern of the isolates by rapid haemagglutination test (RHAT), four (25.00%), one (6.25%), one (6.25%) and one (6.25%) of 16 studied isolates showed hemagglutination activity with rat, hamster, guinea pig and human red blood cells (RBCs), respectively, but none of them could react with mice, rabbits, sheep, goats and chickens RBCs. Based on the fingerprinting of the isolates by enterobacterial repetitive intergenic consensus (ERIC)-PCR, all isolates (100%), without being affected by the type and breed of bird as well as the year and geographical area of separation, showed approximately 19 bands between 120 and 2500 bp and were typed into one genetic pattern (A). Our findings show that all of ORT isolates from commercial poultry in different areas of Iran are very similar in molecular profile, depend on a specific genotype, and are highly similar to genotype A mentioned in research by other scientists.