Establishment of a Bordetella avium challenge model in turkeys

Abstract

Despite the importance of Bordetella avium (BA) as a respiratory pathogen of young turkeys, no infection model for the evaluation of BA-vaccine efficacy is available. The objective of this study was to evaluate the influence of route and dose of infection on the establishment of a BA-challenge model. In our first experiment, 28-day-old turkeys were either inoculated oculonasally with 10, 10 or 10 colony forming units (CFU) of BA per bird or exposed to BA by aerosol with 10-10 CFU/m. The respiratory tract of all inoculated birds was BA-colonized, which was confirmed by choanal swabs and samples of trachea and lung, showing the highest prevalence in the aerosol-inoculated group. BA-specific humoral immune response was detected in the form of IgG in serum from five days post infection (dpi) and IgA in lacrimal fluid from seven dpi. In the second experiment, the model was tested in a vaccination trial. Twenty-one-day-old turkeys were vaccinated with a formalin-inactivated BA vaccine intramuscularly and challenged 21 days post vaccination with 10 CFU per bird oculonasally. BA-specific IgG antibodies were detected in serum and in lacrimal fluid 14 days post vaccination. As in the first experiment, secretory BA-specific antibodies of the IgA isotype were only detected in the inoculated groups from seven dpi. Despite the lack of clinical signs or pathological alterations in both experiments, vaccine efficacy was demonstrated by significant reduction in BA colonization of the trachea (P ≤ 0.05). In our study, a reliable model for BA infection has been established and has been demonstrated to be suitable for evaluation of vaccine efficacy.

Characterization of Temperate LPS-Binding Bordetella avium Phages That Lack Superinfection Immunity

“…Diseased animals show reduced body weight gain due to their poor general condition and a higher susceptibility to various secondary infections ( 3 ). This leads to high economic losses in commercial poultry farms ( 3 , 6 , 10 ), although the disease is characterized by a high morbidity but low mortality ( 11 , 12 ). However, infections are usually treated with antimicrobial agents and, thus, resistant and multidrug-resistant B. avium isolates have recently been reported ( 13 ), demanding new treatment methods.…”

Development of a harmonized method for antimicrobial susceptibility testing of Bordetella avium using broth microdilution and detection of resistance genes

“…Animal Health Association´s Subcommittee on Turkey Health ranked B. avium as the sixth most important issue facing the U.S. turkey production industry (Clark, 2018). Of particular importance, 2-to 6-week-old turkeys show acute respiratory symptoms after infection with B. avium, such as sneezing, beak breathing, tracheal collapse, submandibular oedema and conjunctivitis because of protracted inflammation, while older turkeys suffer from a dry cough (Kelly et al, 1986;Knab et al, 2018;Panigrahy et al, 1981;Register & Jackwood, 2020). Although mortality is quite low, coming in at mostly less than 10%, the rapid spread of B. avium leads to a high morbidity of about 80%-100% within herds (Knab et al, 2018;Register & Jackwood, 2020;Saif et al, 1980).…”

“…Of particular importance, 2-to 6-week-old turkeys show acute respiratory symptoms after infection with B. avium, such as sneezing, beak breathing, tracheal collapse, submandibular oedema and conjunctivitis because of protracted inflammation, while older turkeys suffer from a dry cough (Kelly et al, 1986;Knab et al, 2018;Panigrahy et al, 1981;Register & Jackwood, 2020). Although mortality is quite low, coming in at mostly less than 10%, the rapid spread of B. avium leads to a high morbidity of about 80%-100% within herds (Knab et al, 2018;Register & Jackwood, 2020;Saif et al, 1980). Thought to be transmitted to humans via contaminated poultry meat or other avian reservoirs (Register & Jackwood, 2020), opportunistic B. avium infections have been detected in humans who previously suffered from pneumonia, with symptoms similar to those of B. pertussis or B. bronchiseptica infections; patients with cystic fibrosis are also vulnerable (Harrington et al, 2009;Lavrenko et al, 2020;Spilker et al, 2008).…”

Investigation of the potential of aerosolized Salmonella Enteritidis on colonization and persistence in broilers from day 3 to 21

“…Previously, Cox et al (1996) found that Salmonella administration in broiler chicks through mouth, cloaca, eyes, and nasal passages readily results in seeder birds which may then spread Salmonella throughout the poultry production pen or house. The entry of bacteria from air through the respiratory route in poultry has not been deeply explored, although some studies have examined and confirmed this possibility by performing inoculation of poultry (broilers, turkeys, and layers) with bacterial contaminated aerosol ( Cox et al, 1996 ; Knab et al, 2018 ; Cheng et al, 2020 ) .…”