Phylogenetic characterization of serum plus antibiotic-resistant extraintestinal Escherichia coli obtained from the liver of poultry carcasses in Pernambuco / Caracterização filogenética de Escherichia coli extraintestinal soro- e antibiótico-resistentes isoladas do fígado de carcaças de frango em Pernambuco

In this study, avian extraintestinal Escherichia coli obtained from the liver of poultry carcasses approved for human consumption in the State of Pernambuco-Brazil were tested for antibiotic plus serum-resistance. Liver samples (n=110) were obtained from one slaughterhouse and 88 bacterial isolates were identified as Escherichia coli. The antibiotic-resistance profiles of antibiotics used in human and/or veterinary practice were accessed by the disk-diffusion method. Phenotypes with high resistance to streptomycin (84.0%), tetracycline (44.7%), amikacin (29.8%), gentamicin (21.3%) and ciprofloxacin (21.3%) were identified. Resistance to antibiotics such as ceftazidime, amoxicillin-clavulanic acid and imipenem was also recorded. Twenty isolates with distinct antibiotic-resistance and susceptibility profiles were selected for serum resistance assays, phylogenetic characterization and detection of the iss gene. We have shown that multidrug resistant isolates were often simultaneously resistant to broiler and human sera. Phylogenetic characterization of serum- plus antibiotic-resistant isolates have shown three belonging to group D, eleven to group B1, one to group B2, and five to group A. We concluded that commensal E. coli strains isolated from the liver of healthy poultry carcasses can harbor and potentially share multidrug- plus virulence genes found in pathogenic pathotypes. This suspicion was not related to specific phylogenetic groups or presence of the iss gene.(AU)

Neste estudo, isolados de Escherichia coli extraintestinal aviária obtidos a partir do fígado de carcaças de aves aprovadas para consumo humano no Estado de Pernambuco-Brasil foram testados para resistência a antibióticos e soro. As amostras de fígado (n = 110) foram obtidas de um abatedouro, sendo 88 isolados bacterianos identificados como Escherichia coli. Os perfis de resistência a antibióticos de uso humano e/ou veterinário foram determinados pelo método de disco-difusão. Foram identificados fenótipos com alta resistência à estreptomicina (84,0%), tetraciclina (44,7%), amicacina (29,8%), gentamicina (21,3%) e ciprofloxacina (21,3%). A resistência a antibióticos utilizados na medicina humana e/ou veterinária, tais como a ceftazidima, amoxicilina-ácido clavulânico, estreptomicina e imipenem também foi registrada. Vinte amostras com perfis distintos de resistência/sensibilidade a antibióticos foram selecionadas para os ensaios de resistência ao soro, caracterização filogenética e detecção do gene iss. Foi demonstrado que isolados resistentes a múltiplas drogas foram também simultaneamente resistentes ao soro de frangos e ao soro humano. A caracterização filogenética desses isolados mostraram três pertencentes ao grupo D, onze ao grupo B1, um ao grupo B2 e cinco ao grupo A. Conclui-se que E. coli comensais isoladas do fígado de carcaças de aves saudáveis podem abrigar e potencialmente compartilhar genes de resistência a drogas e de virulência encontrados em patotipos patogênicos. Essa suspeita não foi relacionada com grupos filogenéticos específicos ou com a presença do gene iss.(AU)

Antimicrobial Effect Induced by Fresh Ginger Root Extracts in Broilers.

Poultry is challenged by microbial infection owing to the restrictions in the use of synthetic antibiotic growth promoters. This study investigated the use of ginger, Zingiber officinale Roscoe (family Zingiberaceae) for the control of infections in poultry. Aqueous extracts of fresh ginger was administered to the birds by dispersing in water. A completely randomized experimental design using 100 day old broiler chicks distributed to two treatments having five replicate per treatment. The ginger extract was given to a set of 50 day old birds (ginger treatment 2) and was not added in a second set, which served as the control. The population of microbes (Lactobacillus, Salmonella, E. coli and coliforms) in the crop, ileum and caecum of the birds were determined 7 days before and 7 days after the administration of the fresh ginger extract. Before the administration of ginger, Salmonella population was highest at the crop 1.852 Log cfu/g and decreased afterwards being 1.744 Log cfu/g at the ileum and 1.710 Log cfu/g at the caecum. E. coli was 1.789, 1.821 and 1.727 Log cfu/g at the crop, ileum and caecum respectively. E. coli accounted for over 90% of the coliform population, hence they exhibited the same pattern was observed. Lactobacillus was highest at the crop (1.933 Log cfu/g) and declined through the ileum (1.842 Log cfu/g) to the caecum (1.705 Log cfu/g). The administration of aqueous extract of ginger resulted in a significant decline of all microbial species analyzed over the control (P<0.05). Hence, it is recommended that the use of ginger for the control of infection is plausible but its use must be modified to prevent killing of beneficial microbes in the broiler GIT. The proximate composition of the fresh ginger rhizome used in the study was also presented.