RESUMEN
Respiratory pathogens are difficult to control in large-scale turkey production. This report describes a clinical trial of antimicrobial ovoTF aerosol on a large Belgian turkey farm. ovoTF was administered to reduce Chlamydia psittaci (C. psittaci) infections and to study the impact of this action on the occurrence of Ornithobacterium rhinotracheale (O. rhinotracheale) and avian metapneumovirus (aMPV) infections. Two subsequent broods were included; (i) a control brood receiving no ovoTF and (ii) an ovoTF brood receiving ovoTF aerosol (5mg/animal) at the age of 2 weeks, continuing daily for 12 days. Twenty-four one-day-old toms of the control and ovoTF brood were tagged and monitored for 15 weeks. The control brood experienced two periods of respiratory disease, the first (2-3 weeks of age) due to C. psittaci and the second (8-17 weeks of age) in the presence of C. psittaci, O. rhinotracheale and maybe aMPV. Extensive antibiotic treatment was needed in 2, 8 and 9 week-old toms. In the ovoTF brood, toms stayed healthy until the age of 9 weeks, whereafter respiratory disease occurred in the presence of C. psittaci, O rhinotracheale and aMPV. OvoTF administration: (i) reduced the amount of C. psittaci in the air as demonstrated by bioaerosol monitoring, (ii) prevented respiratory disease during the first half of the brood period, (iii) was associated with 46% reduction of mortality, and (iv) reduced the antibiotic cost. Our results justify additional clinical trials to explore the use of this innovative antimicrobial strategy for poultry.
Asunto(s)
Conalbúmina/uso terapéutico , Infecciones por Flavobacteriaceae/veterinaria , Infecciones por Paramyxoviridae/veterinaria , Enfermedades de las Aves de Corral/tratamiento farmacológico , Psitacosis/veterinaria , Enfermedades Respiratorias/tratamiento farmacológico , Pavos , Adolescente , Animales , Antibacterianos/uso terapéutico , Chlamydophila psittaci , Femenino , Infecciones por Flavobacteriaceae/complicaciones , Infecciones por Flavobacteriaceae/tratamiento farmacológico , Humanos , Masculino , Metapneumovirus , Ornithobacterium , Infecciones por Paramyxoviridae/complicaciones , Psitacosis/complicaciones , Psitacosis/tratamiento farmacológicoRESUMEN
Two groups of five 1-day-old conventional turkeys were housed in negative pressure stables to become experimentally infected with Avian Metapneumovirus (aMPV) and Ornithobacterium rhinotracheale (ORT) at the age of 3 weeks. However, during the first 2 weeks, turkeys started to show respiratory disease characterized by rhinitis and dyspnoea. Routine bacterial and viral diagnoses remained negative. Therefore, pharyngeal swabs from the turkeys and from the veterinary scientist handling the animals were examined for the presence of Chlamydophila (C.) psittaci by using a combination of cell culture, nested PCR and ompA genotype-specific quantitative real-time PCR, as well as by serology. Results revealed simultaneous transmission of C. psittaci outer membrane protein A (ompA) genotypes D, F and E/B from infected turkeys to the veterinary scientist.
Asunto(s)
Infecciones por Chlamydophila/transmisión , Chlamydophila psittaci/genética , Enfermedades de las Aves de Corral/microbiología , Pavos , Veterinarios , Animales , Infecciones por Chlamydophila/microbiología , Infecciones por Chlamydophila/veterinaria , Chlamydophila psittaci/clasificación , Humanos , Enfermedades de las Aves de Corral/transmisión , ZoonosisRESUMEN
Chlamydophila (C.) psittaci, a category B bioterrorism agent, causes respiratory disease in birds and psittacosis or parrot fever in man. The disease spreads aerogenically and no vaccines are available for either birds or man. Highly sensitive C. psittaci bioaerosol monitoring methods are unavailable. We evaluated: (1) dry filtration for collecting C. psittaci from contaminated air using different samplers and membrane filters, (2) impingement into different liquid collection media by use of the AGI-30 impinger and the BioSampler and (3) impaction into newly designed C. psittaci media utilizing the MAS-100 aerosol impactor. For personal bioaerosol sampling, we recommend the use of a gelatin filter in combination with the IOM inhalable dust sampler at an airflow rate of 2L/min. This allowed the detection of 10 organisms of C. psittaci by both PCR and culture. For stationary bioaerosol monitoring, sampling 1000L of air in 10min with the MAS-100 impactor and ChlamyTrap 1 impaction medium was most efficient and made it possible to detect 1 and 10 C. psittaci organisms by PCR and culture, respectively. ChlamyTrap 1 in combination with the MAS-100 impactor might also be applicable for bioaerosol monitoring of viruses.
Asunto(s)
Microbiología del Aire , Chlamydophila psittaci/aislamiento & purificación , Monitoreo del Ambiente/instrumentación , Monitoreo del Ambiente/métodos , Aerosoles , Movimientos del Aire , Técnicas Bacteriológicas , Filtración/instrumentación , Filtración/métodosRESUMEN
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.
Asunto(s)
Antibacterianos/uso terapéutico , Conalbúmina/uso terapéutico , Enfermedades de las Aves de Corral/prevención & control , Psitacosis/veterinaria , Pavos , Animales , Chlamydophila psittaci , Conalbúmina/administración & dosificación , Relación Dosis-Respuesta a Droga , Psitacosis/prevención & control , Organismos Libres de Patógenos EspecíficosRESUMEN
The effect of ovotransferrin (ovoTF), human lactoferrin (hLF) and bovine lactoferrin (bLF) on the obligate intracellular pathogen Chlamydophila (Cp.) psittaci was evaluated using a model of Buffalo Green Monkey kidney (BGM) cells and HD11 chicken macrophages as artificial hosts. Firstly, the effect of transferrins on the infectivity of the bacteria was evaluated. Pre-incubation of Cp. psittaci with 0.5 to 5 mg/mL ovoTF prior to infecting BGM cells significantly lowered the infection rate (P < 0.05). For both lactoferrins, the infection rate could only be reduced with 5 mg/mL, albeit not significantly as compared to the infection rate created by the untreated bacteria. Secondly, transferrins were tested for their ability to influence bacterial adhesion and entry in HD11 cells. Maximal non-cytotoxic and non-bactericidal concentrations of 0.05 mg/mL ovoTF and 0.5 mg/mL hLF and bLF were used. Overall, ovoTF was more effective than human and bovine LF in inhibiting bacterial irreversible attachment and cell entry and the latter was accompanied by a dose-dependent reduction of actin recruitment at the bacterial entry site. However, once bacteria had entered HD11 cells, transferrins had apparently no effect on intracellular replication. The present findings suggest a possible role for transferrins and especially ovoTF, in preventing avian Cp. psittaci infections.
Asunto(s)
Adhesión Bacteriana/efectos de los fármacos , Infecciones por Chlamydia/veterinaria , Chlamydophila psittaci/efectos de los fármacos , Chlamydophila psittaci/fisiología , Conalbúmina/farmacología , Lactoferrina/farmacología , Macrófagos/microbiología , Animales , Línea Celular , Pollos , Infecciones por Chlamydia/microbiología , Infecciones por Chlamydia/prevención & control , Chlamydophila psittaci/crecimiento & desarrollo , Chlamydophila psittaci/patogenicidad , Relación Dosis-Respuesta a Droga , HumanosRESUMEN
Thirty-six birds from a parrot relief and breeding centre, as well as the manager, were examined for the presence of Chlamydophila psittaci. In the relief unit, 5 of 20 African grey parrots showed depression, ruffled feathers, loss of weight and mild dyspnoea. The birds received no antibiotic treatment. Birds of the breeding unit, 14 blue and gold macaws and 2 green-winged macaws, were healthy. They received doxycycline at the start of each breeding season. The manager complained of shortness of breath but took no medication. Using a nested PCR enzyme immunoassay (EIA), Cp. psittaci was detected in the faeces of all five sick birds, as well as in a nasal and pharyngeal swab from the manager. The veterinarian and her assistant became infected while sampling the parrots, as pharyngeal and nasal swabs from both were positive by nested PCR/EIA after visiting the parrot relief and breeding centre, but they showed no clinical signs of infection. Bacteria could be isolated from three of five nested PCR/EIA-positive birds, the manager and the veterinarian, but not from the veterinary assistant. Using an ompA genotype-specific real-time PCR, Cp. psittaci genotype E/B was identified as the transmitted strain. All breeding birds tested negative for Cp. psittaci. This is believed to be the first report on Cp. psittaci genotype E/B transmission from parrots to humans. In contradiction to genotype A strains, which are thought to be highly virulent to both birds and men, the currently described genotype E/B strain apparently caused no severe clinical symptoms in either parrots or humans.
Asunto(s)
Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/transmisión , Portador Sano/epidemiología , Portador Sano/transmisión , Chlamydophila psittaci/clasificación , Brotes de Enfermedades , Heces/microbiología , Enfermedades Profesionales/epidemiología , Loros/microbiología , Psitacosis/veterinaria , Crianza de Animales Domésticos , Técnicos de Animales , Animales , Bélgica/epidemiología , Enfermedades de las Aves/patología , Portador Sano/microbiología , Chlamydophila psittaci/genética , Chlamydophila psittaci/aislamiento & purificación , ADN Bacteriano/genética , Transmisión de Enfermedad Infecciosa , Disnea/patología , Femenino , Humanos , Técnicas para Inmunoenzimas , Masculino , Mucosa Nasal/microbiología , Enfermedades Profesionales/microbiología , Enfermedades Profesionales/patología , Faringe/microbiología , Reacción en Cadena de la Polimerasa , Psitacosis/epidemiología , Psitacosis/patología , Psitacosis/transmisión , Especificidad de la Especie , VeterinariosRESUMEN
We studied zoonotic transmission of Chlamydophila psittaci in 39 breeding facilities for Psittaciformes (cockatoos, parrots, parakeets, lories) that frequently used antimicrobial drugs. Genotypes A or E/B were detected in 14.9% of humans at these facilities. Information on antimicrobial drug use in Psittaciformes and a C. psittaci vaccine are urgently required.