Avian bordetellosis: a significant bacterial respiratory disease of turkeys (Meleagris gallopavo)

Abstract

This review was designed to spotlight on avian bordetellosis regarding the bacterium pathogenesis, susceptibility, transmission, pathology, laboratory diagnosis, and prevention and control measures. Bordetellosis (moreover called turkey coryza) is a contagious bacterial upper respiratory disease of poultry, especially turkey poults. The disease is characterized by high morbidity and low mortality with terrible economic losses for turkeys industry. Bordetellosis is caused by Bordetella avium (B. avium) bacterium which colonizes and destructs the cilia of the respiratory tract. Concurrent infection during bordetellosis outbreaks is common and contributes to the poor performance of B. avium-infected flocks. Domesticated and wild birds are susceptible to bordetellosis. All ages can get infection with bordetellosis, however, young ages are more susceptible than adult. Infection and transmission of B. avium occurs through aerosol, water, and reservoirs, but not vertically. The clinical picture of bordetellosis is usually upper respiratory, except in complications with other bacteria or stressors, the infection extends to the lower respiratory tract. The bacterium is isolated aerobically on 10% sheep blood agar and appears as Gram negative bacilli. Endotoxin, tracheal cytotoxin, heat-labile dermonecrotic toxin, and osteotoxin are produced by B. avium. Antibiotic treatment of B. avium shows variable results and it is usually ineffective. Different types of living and inactivated vaccines are used to prevent bordetellosis.