title: Evaluation of the prophylactic use of ovotransferrin against chlamydiosis in SPF turkeys.
abstract: Chlamydophila (C.) psittaci infections are highly prevalent in turkeys and the economical and public health importance of these infections has been recognized since 1950. As there are no vaccines, antibiotic treatment (tetracylines, enrofloxacine) is often needed to allow marketing of poultry. In this study, we explored the use of ovotransferrin (ovoTF), a natural anti-microbial protein, in preventing an experimental C. psittaci infection in specific pathogen free (SPF) turkeys. Turkeys were treated with aerosolized ovoTF prior to the infection. Groups 1 and 2 received a single dose of 10 and 5 mg ovoTF per turkey, respectively. Group 3 received a daily dose of 5mg ovoTF per turkey during 12 days. Group 4 served as untreated, infected control group. Turkeys were aerosol infected using 10(6) TCID(50) of the virulent C. psittaci serovar/genotype D strain 92/1293. Birds were monitored (clinical signs, bacterial excretion) during 12 subsequent days before being necropsied. At necropsy, pathology and C. psittaci replication in various tissues was examined. A single dose of 10mg ovoTF and a repeated daily dose of 5mg ovoTF could not prevent the birds from becoming infected with C. psittaci, but they significantly reduced the outcome of the infection. A single dose of 5mg ovoTF had no influence on the outcome of the infection as compared to the non-treated infected controls. Our results demonstrate the anti-chlamydial effect of ovoTF in vivo and present a base for further research on practical applications of ovoTF on turkey farms.
authors.affiliation: Department of Molecular Biotechnology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Ghent, Belgium. Caroline.VanDroogenbroeck@UGent.be
authors.forename: Caroline
authors.initials: C
authors.lastname: Van Droogenbroeck
authors.forename: Delphine S A
authors.initials: DS
authors.lastname: Beeckman
authors.forename: Taher
authors.initials: T
authors.lastname: Harkinezhad
authors.forename: Eric
authors.initials: E
authors.lastname: Cox
authors.forename: Daisy
authors.initials: D
authors.lastname: Vanrompay
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002691:Chlamydophila psittaci; D003207:Conalbumin / Q000008:administration & dosage / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D011201:Poultry Diseases / Q000517:prevention & control*; D009956:Psittacosis / Q000517:prevention & control / Q000662:veterinary*; D013047:Specific Pathogen-Free Organisms; D014422:Turkeys
chemical_list: D000900:Anti-Bacterial Agents; D003207:Conalbumin