PREVALENCE AND ANTIMICROBIAL RESISTANCE OF SALMONELLA SEROVARS FROM CHICKEN CARCASSES IN NORTHERN GREECE

This study was conducted to determine the prevalence and antimicrobial resistance of Listeria monocytogenes recovered from chicken carcasses in slaughterhouses in Northern Greece. A total of 100 poultry samples (300 carcasses) were examined for Listeria spp. The samples were neck skin taken from four different slaughterhouses in Northern Greece. Forty samples were also taken from the environment of the slaughterhouses. Identification of L. monocytogenes was carried out by PCR and fingerprinting of the isolates by random amplified polymorphic DNA. L. monocytogenes strains isolated from chicken carcasses and from the environment of the slaughterhouses were also examined for antibiotic resistance. Fifty-five isolates of L. monocytogenes were tested for susceptibility to 20 antibiotics using the disk diffusion method. Listeria spp. were present in 99 of the poultry samples tested (99%), and 38 yielded L monocytogenes (38%). L. monocytogenes was also isolated in 80% of samples from the environment of a certain slaughterhouse, while the other slaughterhouses were found to be contaminated only with Listeria spp. All isolates were resistant to nalidixic acid and oxolinic acid, the majority of them to clindamycin, and only a few to tetracycline and oxytetracycline, whereas they were found to be susceptible to all other antimicrobials. The results of this study demonstrate a high prevalence of L. monocytogenes contamination in chicken carcasses, and all isolates were found to be sensitive to the antimicrobials most commonly used to treat human listeriosis

PREVALENCE AND ANTIMICROBIAL RESISTANCE OF SALMONELLA SEROVARS FROM CHICKEN CARCASSES IN NORTHERN GREECE

This study was conducted to determine the prevalence and antimicrobial resistance of Listeria monocytogenes recovered from chicken carcasses in slaughterhouses in Northern Greece. A total of 100 poultry samples (300 carcasses) were examined for Listeria spp. The samples were neck skin taken from four different slaughterhouses in Northern Greece. Forty samples were also taken from the environment of the slaughterhouses. Identification of L. monocytogenes was carried out by PCR and fingerprinting of the isolates by random amplified polymorphic DNA. L. monocytogenes strains isolated from chicken carcasses and from the environment of the slaughterhouses were also examined for antibiotic resistance. Fifty-five isolates of L. monocytogenes were tested for susceptibility to 20 antibiotics using the disk diffusion method. Listeria spp. were present in 99 of the poultry samples tested (99%), and 38 yielded L monocytogenes (38%). L. monocytogenes was also isolated in 80% of samples from the environment of a certain slaughterhouse, while the other slaughterhouses were found to be contaminated only with Listeria spp. All isolates were resistant to nalidixic acid and oxolinic acid, the majority of them to clindamycin, and only a few to tetracycline and oxytetracycline, whereas they were found to be susceptible to all other antimicrobials. The results of this study demonstrate a high prevalence of L. monocytogenes contamination in chicken carcasses, and all isolates were found to be sensitive to the antimicrobials most commonly used to treat human listeriosis

Lactic Acid Bacteria Isolated from Chicken Carcasses with Inhibitory Activity against Salmonella spp. and Listeria monocytogenes

Lactic acid bacteria (LAB) isolated from poultry carcasses were added to BHI broth along with Salmonella spp. and Listeria monocytogenes in order to determine their antagonistic activity against the pathogens. There was a statistically significant reduction in Salmonella population on the 5th day that varied from 0.41 to 1.12 log CFU/ml. The reduction in L. monocytogenes population was also statistically significant and varied from 0.77 to 1.48 log CFU/ml. The LAB strain with the best inhibitory activity was chosen to examine its action against the same pathogens on the chicken skin and meat. On the chicken skin, the growth reduction on the 6th day caused by L. salivarius was lower and did not exceed the 0.54 log CFU/cm2 for Salmonella spp. and 0.71 log CFU/cm2 for L. monocytogenes. The reduction on the chicken meat was slightly lower for both pathogens. The results of the experiments suggest that L. salivarius (strain LAB 59) has a potential to be used as a protective culture to improve the safety and extend the shelf life of chicken products

Lactic Acid Bacteria Isolated from Chicken Carcasses with Inhibitory Activity against Salmonella spp. and Listeria monocytogenes

Lactic acid bacteria (LAB) isolated from poultry carcasses were added to BHI broth along with Salmonella spp. and Listeria monocytogenes in order to determine their antagonistic activity against the pathogens. There was a statistically significant reduction in Salmonella population on the 5th day that varied from 0.41 to 1.12 log CFU/ml. The reduction in L. monocytogenes population was also statistically significant and varied from 0.77 to 1.48 log CFU/ml. The LAB strain with the best inhibitory activity was chosen to examine its action against the same pathogens on the chicken skin and meat. On the chicken skin, the growth reduction on the 6th day caused by L. salivarius was lower and did not exceed the 0.54 log CFU/cm2 for Salmonella spp. and 0.71 log CFU/cm2 for L. monocytogenes. The reduction on the chicken meat was slightly lower for both pathogens. The results of the experiments suggest that L. salivarius (strain LAB 59) has a potential to be used as a protective culture to improve the safety and extend the shelf life of chicken products