Ornithobacteriosis (ORT) is an acute, contagious bacterial disease caused by
Ornithobacterium rhinotracheale, which has been isolated from commercial and backyard flocks of chickens worldwide.
O. rhinotracheale is a Gram-negative, rod-shaped, highly contagious bacterium that has been isolated from a number of domestic and wild avian hosts.
Infection with
O. rhinotracheale is primarily associated with the respiratory system, but can sometimes cause ear or joint infections. Concurrent infections with other pathogens also impact the severity and range of signs, duration of the disease, and mortality rate in outbreaks of flocks. Respiratory lesions associated with
O. rhinotracheale are similar to many other bacteria, including
E. coli, Pasteurella multocida, R. anatipestifer, Avibacterium paragallinarum, and
Chlamydophyla psittaci.
Transmission
O. rhinotracheale is transmitted to susceptible chickens via horizontal and vertical routes. Chickens can become infected through direct and indirect contact through fomites, feed and water, or aerosols. Since wild birds can be carriers of
O. rhinotracheale, contamination of the flock's environment with feces from wild birds is a common source of introduction.
Diagnosis
Since the clinical signs and postmortem lesions of
O. rhinotracheale are similar to many other bacterial and viral infections, in order for your veterinarian to obtain a definitive diagnosis, they will need to send samples from certain organs to a diagnostic lab which offer
O. rhinotracheale testing in order to isolate and identify the causative agent. This may be achieved through the following diagnostics:
- Bacterial Isolation and Identification: The trachea or lungs are the best tissues to isolate O. rhinotracheale from. The infraorbital sinus and nasal cavity are also suitable for culture.
- Antigen Detection: PCR testing of tracheal swabs may be useful for detecting O. rhinotracheale.
- Serological tests: The presence of antibodies against O. rhinotracheale can be detected by ELISA, if taken within 1 to 4 weeks after the bird was first infected.
Treatment
O. rhinotracheale is somewhat inconsistent in sensitivity to antibiotics, and varies depending on the source of the strain. However, there has been some success with chlortetracycline, amoxicillin, and tylosin.