RESUMEN
Campylobacter fetus causes severe infections in humans and can be isolated from various mammals and reptiles. However, although poultry are considered to be the main reservoir of Campylobacter jejuni, little is known about the presence of C. fetus in poultry. Thus, specific pathogen-free chickens were experimentally inoculated with a mixture of either three non-thermotolerant or four thermotolerant human strains of C. fetus. Faecal samples were regularly sampled after inoculation and caeca and intestines were collected 21 or 40 days after inoculation. All samples were analysed for the presence of Campylobacter using culture techniques. No Campylobacter could be re-isolated. This result strongly suggests that broilers do not play an important part in the C. fetus contamination of humans.
Asunto(s)
Infecciones por Campylobacter/microbiología , Infecciones por Campylobacter/transmisión , Campylobacter fetus/aislamiento & purificación , Pollos/microbiología , Reservorios de Enfermedades/microbiología , Microbiología de Alimentos , Animales , Ciego/microbiología , Heces/microbiología , Humanos , Intestinos/microbiología , Organismos Libres de Patógenos EspecíficosRESUMEN
Mycoplasma synoviae infection occurs worldwide in commercial poultry flocks and may result in severe economic losses. The prevalence of this mycoplasma in standard layers older than 60 weeks was studied in a French department and the characteristics of infected or free flocks were compared. The genomic profiles of isolates from 36 infected flocks were studied by pulsed-field gel electrophoresis and random amplified polymorphic DNA methods in order to investigate possible routes of transmission. The minimum inhibitory concentrations of antibiotics were determined. Results showed that infection was more frequent in multi-age farms. Egg production and mortality of infected flocks were respectively lower and higher than in non-infected flocks but the differences were not statistically significant. The genomic profiles of isolates were quite homogeneous, a feature which does not facilitate the understanding of routes of transmission. All isolates were susceptible to tetracyclines, macrolides (except erythromycin), spectinomycin and fluoroquinolones.
Asunto(s)
Pollos , Infecciones por Mycoplasma/veterinaria , Mycoplasma synoviae/genética , Mycoplasma synoviae/aislamiento & purificación , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/microbiología , Animales , Antibacterianos/farmacología , Cartilla de ADN/química , Electroforesis en Gel de Campo Pulsado/veterinaria , Femenino , Francia/epidemiología , Genoma Bacteriano/genética , Pruebas de Sensibilidad Microbiana/métodos , Pruebas de Sensibilidad Microbiana/veterinaria , Infecciones por Mycoplasma/epidemiología , Infecciones por Mycoplasma/transmisión , Mycoplasma synoviae/efectos de los fármacos , Enfermedades de las Aves de Corral/transmisión , Prevalencia , Técnica del ADN Polimorfo Amplificado Aleatorio/veterinariaRESUMEN
OBJECTIVES: The antimicrobial susceptibility of Campylobacter strains isolated from standard and free-range broilers in 1992-1996 and 2001-2002 was studied. METHODS: Strains were isolated from caeca or skin samples collected from standard or free-range broilers arriving in slaughterhouses. The MICs of ampicillin, nalidixic acid, enrofloxacin, tetracycline, erythromycin and gentamicin were determined by agar dilution and compared according to species (Campylobacter jejuni or Campylobacter coli), production system and sampling period. RESULTS: Results showed that all chickens harboured Campylobacter. An increase over time of the C. coli/C. jejuni ratio for standard chickens occurred. A wide range of MICs was observed among isolates from the same broiler or from the same farm. Strains collected on entry to the slaughterhouse and after storage showed no significant difference in their antibiotic resistance. C. coli was more resistant than C. jejuni to tetracycline and erythromycin during the first period and to all tested molecules (except gentamicin) during the second period. Strains isolated from standard chickens were also more often resistant than those isolated from free-range broilers. The percentage of C. jejuni strains resistant to ampicillin decreased from 1992-1996 to 2001-2002, whereas no change could be observed for the other antimicrobial agents. However, for C. coli the resistance to ampicillin, nalidixic acid, enrofloxacin, tetracycline and erythromycin significantly increased. CONCLUSION: There was an increase in the incidence of antibiotic resistance of C. coli between 1992-1996 and 2001-2002.
Asunto(s)
Antibacterianos/administración & dosificación , Infecciones por Campylobacter/veterinaria , Campylobacter coli/efectos de los fármacos , Campylobacter jejuni/efectos de los fármacos , Farmacorresistencia Bacteriana , Legislación Veterinaria , Enfermedades de las Aves de Corral/microbiología , Alimentación Animal , Animales , Antibacterianos/farmacología , Infecciones por Campylobacter/microbiología , Campylobacter coli/aislamiento & purificación , Campylobacter jejuni/aislamiento & purificación , Pollos , Francia , Pruebas de Sensibilidad MicrobianaRESUMEN
The polymerase chain reaction (PCR) was used to detect Mycoplasma gallisepticum in samples collected from the environment of experimentally or naturally infected poultry. Culture was also used in the experimental infections. Of 160 samples of food, drinking water, feathers, droppings or dust collected during experimental infection, 103 were positive using a M. gallisepticum-specific PCR (MG-PCR) and 68 were positive using a PCR (mycoplasma-PCR) that detects all species of the genera Mycoplasma, Spiroplasma, Acholeplasma and Ureaplasma. Six of these samples were also positive by culture. In environmental samples collected on a depopulated M. gallisepticum-positive turkey farm, three and two out of a total of 12 were positive by mycoplasma-PCR and MG-PCR, respectively. These results indicate the disseminating capacity of this mycoplasma and the possible use of PCR methods for epidemiological analyses and control of farm decontamination before the introduction of new birds.