RESUMO

Background: The genus Salmonella, associated with poultry products, is considered the leading cause of foodborne outbreaks in humans in many countries. In Brazil, Salmonella Enteritidis (SE) is the serovar remains as one most frequentlyisolated from humans, and it is also a major serovar found in animals, food, animal feed, and environmental samples, despiteall the efforts to control this pathogen. Also, the bacterium is able to form biofilms on different surfaces, protecting cellsfrom both cleaning and sanitizing procedures in the food industries. This study aimed to verify the ability of SalmonellaEnteritidis isolates to form biofilm on polystyrene at different incubation temperatures.Materials, Methods & Results: A total of 171 SE samples were isolated from foodborne outbreaks (foods and stool cultures) and poultry products between 2003 and 2010. The biofilm-forming ability of samples was measured at four differenttemperatures (3°C, 9ºC, 25ºC, and 36ºC), for 24 h, simulating temperatures usually found in poultry slaughterhouses. Later,200 μL of each bacterial suspension was inoculated, in triplicate, onto 96-well, flat-bottomed sterile polystyrene microtiterplates, washed, after that, the biofilm was fixed with methanol. The plates were dried at ambient temperature, stained with2% Huckers crystal violet. Afterwards, absorbance was read using an ELISA plate reader and the optical density (OD)of each isolate was obtained by the arithmetic mean of the absorbance of three wells and this value was compared withthe mean absorbance of negative controls (ODnc). The following classification was used for the determination of biofilmformation: no biofilm production, weak biofilm production, moderate biofilm production and strong biofilm production.Results demonstrated all isolates from stool cultures and foods involved in foodborne outbreaks, at least one of the fourtemperatures tested, were able to form biofilm...(AU)

Assuntos

RESUMO

Background: The genus Salmonella, associated with poultry products, is considered the leading cause of foodborne outbreaks in humans in many countries. In Brazil, Salmonella Enteritidis (SE) is the serovar remains as one most frequentlyisolated from humans, and it is also a major serovar found in animals, food, animal feed, and environmental samples, despiteall the efforts to control this pathogen. Also, the bacterium is able to form biofilms on different surfaces, protecting cellsfrom both cleaning and sanitizing procedures in the food industries. This study aimed to verify the ability of SalmonellaEnteritidis isolates to form biofilm on polystyrene at different incubation temperatures.Materials, Methods & Results: A total of 171 SE samples were isolated from foodborne outbreaks (foods and stool cultures) and poultry products between 2003 and 2010. The biofilm-forming ability of samples was measured at four differenttemperatures (3°C, 9ºC, 25ºC, and 36ºC), for 24 h, simulating temperatures usually found in poultry slaughterhouses. Later,200 μL of each bacterial suspension was inoculated, in triplicate, onto 96-well, flat-bottomed sterile polystyrene microtiterplates, washed, after that, the biofilm was fixed with methanol. The plates were dried at ambient temperature, stained with2% Hucker’s crystal violet. Afterwards, absorbance was read using an ELISA plate reader and the optical density (OD)of each isolate was obtained by the arithmetic mean of the absorbance of three wells and this value was compared withthe mean absorbance of negative controls (ODnc). The following classification was used for the determination of biofilmformation: no biofilm production, weak biofilm production, moderate biofilm production and strong biofilm production.Results demonstrated all isolates from stool cultures and foods involved in foodborne outbreaks, at least one of the fourtemperatures tested, were able to form biofilm...

Assuntos

RESUMO

The Magdalena River Turtle, Podocnemis lewyana, is an endangered and endemic turtle from Colombia. Among the most important information needed to conserve endangered species is to identify, monitor, and protect the sites used by the species to reproduce and grow. In this study we report, for the first time, the reproductive output and the nesting beaches of P. lewyana in the Claro Cocorná Sur River, a tributary of the Magdalena River drainage. We systematically examined a river transect of 8 km with 14 sandy beaches during two nesting seasons in one year. We recorded a yearly production of 47 clutches, 957 eggs, and two preferred nesting beaches: Alto Bonito with 51 %, and Bélgica with 28.3 % of this reproductive output. AAFUVER, a community-based organization, has led a headstarting program since 2010 to decrease in-situ egg mortality due to predation on nesting beaches. AAFUVER collects and incubates the eggs ex-situ, raises the hatchlings for one to five months and then releases them into the same river. To understand potential effects of such egg manipulation, we monitored and compared in-situ and ex-situ incubation temperatures. We found ex-situ temperatures below the pivotal temperature known for P. lewyana and below the temperatures in nesting beaches. Finally, we monitored hatchlings growth under AAFUVER captive conditions, and found that hatchlings duplicated their body mass during the first three months of age. Egg weight was strongly associated to body weight at hatching, however this association is lost by the third month of age. We strongly encourage supporting this community-based conservation program, and the protection of the Claro Cocorná Sur River as an important nesting and growth habitat for the conservation of P. lewyana.

La tortuga del Río Magdalena, Podocnemis lewyana, es una tortuga categorizada como amenazada y además endémica colombiana. Dentro de la información más necesaria para entender el estado de conservación de estas especies está el identificar, monitorear y proteger sus sitios de reproducción y crecimiento. En este estudio se reporta, por primera vez, el potencial reproductivo y las principales playas de anidación de P. lewyana en el río Claro Cocorná Sur, un tributario del río Magdalena. Un trayecto de 8 km del río que albergaba 14 playas arenosas fueron monitoreados sistemáticamente durante dos estaciones de anidación en un año. Durante este tiempo se registraron 47 nidos, 957 huevos y dos playas de mayor anidación: Alto Bonito con el 51 %, y Bélgica con el 28,3 % de dicha producción anual. AAFUVER, una organización de la comunidad local, ha liderado un programa de reforzamiento poblacional para disminuir la mortalidad de los huevos incubados in-situ. AAFUVER colecta e incuba los huevos ex-situ, cría los neonatos durante uno a cinco meses, y los libera en el río de origen. Para entender los efectos potenciales de esta manipulación de los huevos las temperaturas de incubación in-situ y ex-situ fueron monitoreadas y comparadas. Se encontró que las temperaturas ex-situ son inferiores a la temperatura pivotal de P. lewyana y a las temperaturas en las playas de anidación. Finalmente, se reporta el crecimiento corporal de los tortuguillos dadas las condiciones de cautiverio de AAFUVER. Se encontró una fuerte asociación entre el peso del huevo y el peso de los neonatos a los siete días de edad, sin embargo esta asociación se perdió a los tres meses de edad. Nosotros enfatizamos en la importancia de apoyar este programa de conservación liderado por la comunidad local, y la protección del Río Claro Cocorná Sur como un hábitat importante de anidación y crecimiento de P. lewyana.