title: Evaluation of antimicrobial treatment in a bovine model of acute Chlamydia psittaci infection: tetracycline versus tetracycline plus rifampicin.
abstract: Antimicrobial treatment of chlamydial infections is known to be of limited efficacy. In this study, effects of doxycycline (D), usually the drug of choice, were compared with the combined therapy of doxycycline and rifampicin (R) in a bovine model of respiratory Chlamydia psittaci infection. After intrabronchial inoculation of the pathogen, 30 animals were assigned to five groups (n = 6 per group): untreated controls, monotherapy with D (5 mg kg(-1)day(-1) or 10 mg kg(-1)day(-1)), and combination therapy of D and R (600 mg day(-1)). Treatment continued until day 14 post inoculation (d.p.i.). Clinical signs, inflammatory markers, and pathological findings confirmed successful infection in all animals. Reisolation of the pathogen was possible in 4/6 untreated animals and in 4/12 animals treated with D alone until 4 d.p.i., but in none of the calves of the two D + R groups. Pathogen detection was possible in all animals without significant differences among groups. Severity of disease and time course of its resolution, assessed by clinical and pathological findings as well as inflammatory parameters, were not significantly different between untreated controls and calves receiving D alone or in combination with R. Regardless of the treatment regimen, all groups recovered clinically and cleared the infection within 2 weeks.
authors.affiliation: Institute of Molecular Pathogenesis at Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Prohl
authors.affiliation: Institute of Molecular Pathogenesis at Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Lohr
authors.affiliation: Institute of Molecular Pathogenesis at Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany.
authors.forename: Carola
authors.initials: C
authors.lastname: Ostermann
authors.affiliation: Institute of Molecular Pathogenesis at Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Liebler-Tenorio
authors.affiliation: Institute of Molecular Pathogenesis at Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany.
authors.forename: Angela
authors.initials: A
authors.lastname: Berndt
authors.affiliation: Institute of Bacteriology and Mycology, Veterinary Faculty at The University of Leipzig, Leipzig, Jena, Germany.
authors.forename: Wieland
authors.initials: W
authors.lastname: Schroedl
authors.affiliation: LIPIDOMIX GmbH, Berlin, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Rothe
authors.affiliation: Institute of Molecular Pathogenesis at Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany OIE Reference Laboratory for Chlamydiosis at Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany.
authors.forename: Evelyn
authors.initials: E
authors.lastname: Schubert
authors.affiliation: Institute of Molecular Pathogenesis at Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany OIE Reference Laboratory for Chlamydiosis at Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany.
authors.forename: Konrad
authors.initials: K
authors.lastname: Sachse
authors.affiliation: Institute of Molecular Pathogenesis at Friedrich-Loeffler-Institut (Federal Research Institute for Animal Health), Jena, Germany petra.reinhold@fli.bund.de.
authors.forename: Petra
authors.initials: P
authors.lastname: Reinhold
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000166:cytology; D002417:Cattle; D002691:Chlamydophila psittaci / Q000187:drug effects*; D004195:Disease Models, Animal; D004318:Doxycycline / Q000008:administration & dosage*; D004359:Drug Therapy, Combination / Q000379:methods; D008168:Lung / Q000473:pathology; D008297:Male; D011446:Prospective Studies; D009956:Psittacosis / Q000188:drug therapy* / Q000473:pathology; D012293:Rifampin / Q000008:administration & dosage*; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D004318:Doxycycline; D012293:Rifampin
keywords: Chlamydia psittaci; antimicrobial treatment; bovine model of respiratory infection; doxycycline; rifampicin; tetracycline