Identification and serotyping of Ornithobacterium rhinotracheale

Abstract

In the present study 443 strains of Ornithobacterium rhinotracheale, a causative agent of respiratory disease in fowl, were investigated biochemically and serologically. In both ways O. rhinotracheale could be differentiated from other gram-negative rods and, more particularly, from the Pasteurella-like bacteria potentially pathogenic for fowl. For the biochemical characterization of O. rhinotracheale the API 2ONE identification strip proved to be useful, although O. rhinotracheale is not included in the API system. Serologically, by using monovalent antisera in agar gel precipitation (AGP) tests and enzyme-linked immunosorbent assays (ELISAs), seven serotypes (serotypes A to G) of O. rhinotracheale could be discriminated. The AGP test was chosen as the preferred method to be used for serotyping. Isolates of serotype A were found to be the most prevalent, especially in chickens. Isolates from turkeys were more heterogeneously divided over the serotypes. Some strains showed cross-reactivity between serotypes A, B, and E. Five O. rhinotracheale strains could not be serotyped with the available antisera. Relationships between the geographic origin and the serotypes were found. By the ELISA the presence of antibodies against O. rhinotracheale could be detected in 1-day-old birds as well as in birds with clinical signs, and therefore, it might be useful for diagnostic purposes. Respiratory problems, together with purulent pneumonia, airsacculitis, severe growth retardation, and rapidly increasing mortality, were reported in meat turkeys and broilers in South Africa, Germany, the United States, France, and The Netherlands (1, 2, 4, 6). A gram-negative, pleomorphic rod could repeatedly be isolated from affected organs. This Pasteurellalike organism has recently been referred to as Ornithobacterium rhinotracheale gen. nov. sp. nov. (7). In experimental infections, it was possible to evoke severe growth retardation and airsacculitis in turkeys and chickens with this bacterium (8). O. rhinotracheale strains from different countries reporting fowl infected with the organism were investigated for their bacteriological, biochemical, and serological relationships and their differences from other gram-negative rods.

Characterization of Ornithobacterium rhinotracheale field isolates from Hungary

“…Serotyping is the traditional method of distinguishing O. rhinotracheale isolates (van Empel & Hafez, 1999). Consistent with data in the literature (van Empel et al, 1997;Numee et al, 2012), serotype A was the most prevalent serotype among the strains isolated in Hungary in 1997-2015. Most of the isolates from turkeys and those from birds of prey belonged to this group.…”

Seroprevalence of Ornithobacterium rhinotracheale Infection in Broiler and Broiler Breeder Chickens in West Azerbaijan Province, Iran

“…The use of ELISA for the detection of antibodies to O. rhinotracheale has been reported (Hafez and Sting, 1996;van Empel et al, 1997;van Empel and Hafez, 1999). The serotype specificity of the ELISA is a disadvantage, although a number of commercial ELISAs have been described to have high sensitivity to various O. rhinotracheale serotypes (van Empel and Hafez, 1999;Lopes et al, 2000;Heeder et al, 2001).…”

“…As no O. rhinotracheale vaccine is used in Iran, positive reactions in ELISA are indicative of field infections. Because, the commercial ELISA used in this study was able to detect only 12 out of 18 identified O. rhinotracheale serotypes (van Empel et al, 1997), it is possible that some of the O. rhinotracheale infected chicken sera may have remained undetected and level of infection to O. rhinotracheale are much higher.…”

Co-infection of broilers with Ornithobacterium rhinotracheale and H9N2 avian influenza virus

“…ORT can be a primary or secondary etiological agent, depending on the strain virulence, environmental factors, the immune status of the host, and the presence of other infectious agents [1]. In recent years, outbreaks of respiratory disease associated with ORT have been reported all over the world, including the USA, France, Netherlands, Belgium, Spain, Germany, Hungary, Israel, Korea, Japan, Taiwan, Turkey, Brazil, Iran and South Africa [1][2][3][4][5][6][7][8][9]. This pathogen can cause economic losses in the poultry industry due to growth retardation and the designation of infected carcasses as unacceptable for human consumption [1,6,8].…”

“…In recent years, outbreaks of respiratory disease associated with ORT have been reported all over the world, including the USA, France, Netherlands, Belgium, Spain, Germany, Hungary, Israel, Korea, Japan, Taiwan, Turkey, Brazil, Iran and South Africa [1][2][3][4][5][6][7][8][9]. This pathogen can cause economic losses in the poultry industry due to growth retardation and the designation of infected carcasses as unacceptable for human consumption [1,6,8]. The H9N2 avian influenza virus (AIV) is not only widespread in poultry, but it also has important implications for human health as a zoonotic infection [10,11].…”