Abstract Poultry meat is a food product that usually carries high rates of microbial contamination, including foodborne pathogens. The poultry industry has established different systems to minimize these hazards. In recent years, extensive literature has demonstrated the antimicrobial activity of different contact surfaces made of copper to effectively reduce microbial loads. The aim of the present study was to evaluate the antibacterial effect of copper surfaces on the transmission of two foodborne pathogens – Salmonella enterica and Listeria monocytogenes – and a poultry native microbiota bacterial species – Enterobacter cloacae. We also evaluated the impact of the poultry meat matrix on the antimicrobial activity of a copper surface. Our results indicated that copper surfaces reduced the bacterial load quickly (<than 4 min) when the microorganisms were exposed to polished copper surfaces. Even when bacteria were inoculated on copper surfaces soiled with the organic matrix (washing water from poultry carcasses) and survival rates were significantly higher, an antimicrobial effect was still observed. Survival rates of two microorganisms simultaneously exposed to copper did not show significant differences. We found an antimicrobial effect over pathogenic and non-pathogenic microorganisms. Results suggest a potential role for copper surfaces in the control of microbiological hazards in the poultry industry.

The aims of this study were to determine the occurrence of Listeria monocytogenes in cattle feces and ground beef, to characterize these strains by pulsed-field gel electrophoresis and to compare them to three listeria strains found in humans. Cattle from different origins (n = 250) and ground beef obtained from supermarkets (n = 40) were sampled. The results show low occurrence in cattle feces (0.4 %) but a higher presence in ground beef (37 %). An important part of the ground beef strains (80 %) had > 95 % similarity with a strain isolated from a human sporadic case and the ATCC 19115 used as control. The strain isolated from cattle feces had 93 % similarity to clone 009, previously associated with a listeriosis outbreak related to cheese. Cattle and ground beef can harbor virulent L. monocytogenes strains. Further studies in animals and animal products are needed to improve listeriosis control.

Los objetivos de este estudio fueron determinar la presencia de Listeria monocytogenes en el ganado y en la carne molida de vacuno comercializada en Chile, caracterizar los aislados mediante electroforesis de campo pulsado y compararlos con los obtenidos en tres cepas que han producido listeriosis en humanos, en ese país. Se tomaron muestras de heces de bovinos (n = 250) y de carne molida obtenida en supermercados (n = 40). Se encontró una baja incidencia de este patógeno en las heces de bovinos (0,4 %; un solo animal), pero mayores porcentajes en la carne molida (37 %). Gran parte de las cepas encontradas en la carne molida (80 %) mostraron una similitud mayor del 95 % con un caso esporádico de listeriosis y con la cepa de referencia ATCC 19115. La cepa aislada de bovino tuvo un 93 % de similitud con el clon 009, responsable de un brote asociado al consumo de queso, ocurrido en 2008. Se concluye que el ganado y la carne molida pueden albergar cepas virulentas de L. monocytogenes. Se necesita un mayor número de estudios en animales y en los productos que se obtienen de ellos para mejorar el control de la listeriosis.