Investigação bacteriológica e molecular de salmonella sp. em granjas de postura comercial

• Autor(a) principal: Moraes, Dunya Mara Cardoso
• Data de Publicação: 2014
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/6460
• topic: Antimicrobianos; genes de virulência; ovos; PCR em tempo real; Antimicrobials; Eggs; PCR; Virulence gene; CIENCIAS AGRARIAS::MEDICINA VETERINARIA

The purpose of this research was to investigate presence of Salmonella sp. by conventional bacterial identification and real-time PCR on eggshell, albumen, and yolk of washed and unwashed commercial white and brown eggs; in samples of flooring material from transport crates (meconium); raising environment (swab of cages and drinking fountains); cloacal swab; food and insects from growing, rearing and production phases in a commercial group of laying hens. Also, was examinated the susceptibility profile of Salmonella isolates to 14 antimicrobials: sulfamethoxazole (25μg), trimethoprim-sulfamethoxazole (25μg), enrofloxacin (5μg), tetracyclin (30μg) sulphonamides (300μg), ciprofloxacin (10μg), amoxicillin and clavulanic acid (3μg), ampicillin (20μg), ceftiofur (30μg), gentamicin (10μg), oxytetracycline (30μg), neomycin (30μg), doxycycline (30μg) and apramycin (15μg); and evaluated the presence of virulence gene spvC and resistence genes intl1, sul1 and blaTEM. A total of 68 dozens of white eggs and 61 dozens of brown eggs were randomly collected in poultry houses and 30 dozens and 34 dozens of white and brown eggs, respectively, were collected in egg-storage room (on the farm). Each collected dozen corresponded to three sample units: eggshell, albumen and yolk, totaling 387 samples. Salmonella spp. was detected by conventional bacteriology in 5.4% of analyzed samples and in 16% by qPCR. Salmonella Agona represented 18.2% of identified serovars, Salmonella enterica subs. enterica O:4.5 18.2%, Salmonella Schwarzengrund 18.2%, Salmonella Cerro 13.6%, Salmonella Anatum 13.6%, Salmonella Enteritidis 9.1%, Salmonella Johannesburg 4.5%, Salmonella Corvallis 4.5%, Salmonella Livingstone and Salmonella Senftenberg. From 864 samples collected (248 samples originated from growing, 392 from rearing and 224 from production phase), 2,8% where positives in bacteriologic technique and 15,3% in qPCR. Contamination was higher in growing and rearing phases and declined in production phase. Twenty four isolations of Salmonella where typified as Salmonella Agona (41,7%), Salmonella Livingstone (33,3%), Salmonella Cerro (16,7%), Salmonella Senftenberg (4,2%) and Salmonella Schwarzengrund (4,2%). The highest resistance percentage observed were to sulfamethoxazole (91,0%), sulphonamides (51%) and ceftiofur (28,9%) and 0% to ciprofloxacin. Only Salmonella Johannesburg and Salmonella Corvallis showed resistance to only one antibiotic and others serovars were resistant to at least two antimicrobials, noting that Salmonella Schwarzengrund presented resistance to 13 of them. The gene spvC was dectected only in serovar Enteritidis, while intl1 was present in six of ten analyzed serovars and the gene sul1 in three of them, always in association with intl1. The gene blaTEM was not identified. In conclusion, this research points numerous serovars circulating in commercial egg structures and phenotypic antimicrobials resistance investigation, along with antimicrobial resistance genes in isolates of Salmonella sp. are important investigation tools to determinate genetic profile of these bacteria.