Intraspecies Genetic Variability of Ornithobacterium rhinotracheale in Commercial Birds in Peru

Abstract

Strains of the bacterium Ornithobacterium rhinotracheale (ORT), a causal agent of respiratory diseases in birds, were microbiologically isolated, identified, and molecularly characterized. Blood-enriched culture media and biochemistry tests were used for microbiologic identification. Polymerase chain reaction (PCR) and repetitive extragenic palindromic PCR (rep-PCR) techniques were used for molecular identification and characterization, respectively, of the microorganism. ORT strains were isolated in enriched media from the trachea and air sacs of broilers, breeders, and layers from several geographic zones of Peru. Of the original 75 strains isolated from 75 clinical samples from which ORT was recovered during 1998-2000, 25 were selected for further study based on ORT as the primary pathogenic isolate (no other pathogens were detected). Selected isolates were molecularly identified and characterized by PCR using specific primers designed from the conserved zones of the 16S ribosomal genes. Primers used for the identification of ORT produced a specific fragment of 784 base pair (bp), which did not appear in Haemophilus paragallinarum or Pasteurella multocida, microorganisms with similar morphologic and biochemical characteristics that produce dinical signs identical to those of ORT. All 25 strains of ORT tested with rep-PCR had a genetic profile similar to that of ORT American Type Culture Collection 51463, indicating the presence of only one genotype in the ORT strains studied.

Molecular identification of Ornithobacterium rhinotracheale in turkeys in Isfahan province of Iran

“…All ORT isolates that were positive by the culture were also detected to be positive by the PCR (Ozbey et al, 2004). Koga et al, (2005) (Ghanbarpour and Salehi, 2009). Since this study was carried out throughout the fall in 2010 (Isfahan, Iran), the higher prevalence of ORT in this study is possible.…”

“…This microorganism is a new poultry pathogen associated with respiratory disease, decreased growth and increased mortality in chickens and turkeys (Chin and Droual, 1997;Hafez, 1996). The name Ornithobacterium was suggested for the new genera within the rRNA super family and the name rhinotracheal was suggested for the species (Koga et al, 2005). The first recorded isolation of ORT was made from turkeys in Germany in 1981 (Banani et al, 2001).…”

“…ORT was reported in the meat of turkeys and broilers in South Africa, Germany, United States, France and Netherlands (Empel et al, 1997). The name Ornithobacterium was suggested for the new genera within the rRNA super family and the name rhinotracheal was suggested for the species (Koga et al, 2005). O. rhinotracheale can cause highly infectious diseases in poultry, but the severity of clinical symptoms, duration of the disease and mortality has been described to be highly variable (Bisgaard et …”

“…Clinical signs associated with ORT infection include tracheitis, airsacculitis pericarditis, sinusitis and exudative pneumonia (Banani et al, 2001). Although microbiologic isolation and identification have been done by several investigators, there are few reports using molecular identification techniques such as polymerase chain reaction (PCR) and 16S ribosomal gene sequencing because identification of ORT is difficult using reliable method (Ozbey et al, 2004;Koga et al, 2005). The aim of this study was to determine the prevalence of ORT in turkeys in Isfahan province of Iran using PCR and bacterial culture methods.…”

Nervous signs associated with otitis and cranial osteomyelitis and withOrnithobacterium rhinotrachealeinfection in red-legged partridges (Alectoris rufa)

“…Differences in pathogenicity have been reported between clinical isolates of ORT (Devriese et al, 1995;Travers et al, 1996;van Veen et al, 2000;Koga & Zavaleta, 2005) so the high mortality in the partridges might have been related to high pathogenicity of the strain involved. Alternatively, partridges could differ from other birds in their susceptibility to ORT.…”