ABSTRACT
AIM: The aim of this study was to provide information on the prevalence of Salmonella serotypes and to identify risk factors for Salmonella spp. contamination in broiler chicken farms and slaughterhouses in the northeast of Algeria. MATERIALS AND METHODS: This study was conducted on 32 poultry farms and five slaughterhouses in the province of Skikda (northeastern Algeria). A questionnaire was answered by the poultry farmers and slaughterhouses' managers. Biological samples (cloacal swabs, droppings, caeca, livers, and neck skins) and environmental ones (water, feed, surface wipes, rinsing water, and sticking knife swabbing) were taken to assess the Salmonella contamination status. RESULTS: Nearly 34.37% of the poultry farms and all the slaughterhouses were contaminated with Salmonella. The isolated Salmonella strains belonged to two major serotypes: Kentucky and Heidelberg followed by Enteritidis, Virginia, and Newport. There was an evident heterogeneous distribution of serotypes in poultry farms and slaughterhouses. Only one factor (earth floor) was significantly associated with Salmonella contamination in poultry houses (p<0.05). CONCLUSION: A high prevalence rate of Salmonella contamination was found in poultry farms and slaughterhouses in Skikda region. These results showed the foremost hazardous role of poultry production in the spread and persistence of Salmonella contamination in the studied region.
ABSTRACT
BACKGROUND: The aims of this study were to investigate Salmonella contamination in broiler chicken farms and slaughterhouses, to assess the antibiotic resistance profile in avian and human Salmonella isolates, and to evaluate the relationship between avian and human Extended Spectrum ß-Lactamase (ESBL)-producing isolates. Salmonella was screened in different sample matrices collected at thirty-two chicken farms and five slaughterhouses. The human isolates were recovered from clinical specimens at the University Teaching Hospital of Constantine (UTH). All suspected colonies were confirmed by MALDI-TOF (Matrix Assisted Laser Desorption Ionization Time OF light) and serotyped. Susceptibility testing against 13 antibiotics including, amoxicillin/clavulanic acid, ticarcillin, cefoxitin, cefotaxime, aztreonam, imipenem, ertapenem, gentamicin, amikacin, ciprofloxacin, colistin, trimethoprim/sulfamethoxazole and fosfomycin, was performed using the disk diffusion method on Mueller-Hinton agar. ESBL-production was screened by the double-disk synergy test and confirmed by molecular characterization using PCR (polymerase chain reaction) amplification and sequencing of ESBL encoding genes. Clonality of the avian and human strains was performed using the Multi Locus Sequencing Typing method (MLST). RESULTS: Forty-five isolated avian Salmonella strains and 37 human collected ones were studied. Five S. enterica serotypes were found in avian isolates (mainly Kentucky) and 9 from human ones (essentially Infantis). 51.11% and 26.6% of the avian isolates were resistant to ciprofloxacin and cefotaxime, respectively, whereas human isolates were less resistant to these antibiotics (13.5% to ciprofloxacin and 16.2% to cefotaxime). Eighteen (12 avian and 6 human) strains were found to produce ESBLs, which were identified as bla CTX-M-1 (n = 12), bla CTX-M-15 (n = 5) and bla TEM group (n = 8). Interestingly, seven of the ESBL-producing strains (5 avian and 2 human) were of the same ST (ST15) and clustered together, suggesting a common origin. CONCLUSION: The results of the combined phenotypic and genotypic analysis found in this study suggest a close relationship between human and avian strains and support the hypothesis that poultry production may play a role in the spread of multidrug-resistant Salmonella in the human community within the study region.
