Comparison of polymerase chain reaction and bacterial culture for Salmonella detection in the Muscovy duck in Trinidad and Tobago / Comparación de la reacción en cadena de la polimerasa y el cultivo bacteriano como métodos de detección de Salmonella en patos criollos en Trinidad y Tobago

OBJECTIVES: The purpose of this study was to investigate the presence and serovar identity of Salmonella, at the national level, in farmed Muscovy ducks (Cairina moschata) in Trinidad and Tobago, and to compare the relative benefits of bacterial culture to those of polymerase chain reaction (PCR) for use in the routine detection and surveillance of Salmonella in these ducks. METHODS: From March-September 2003, 110 fecal samples were collected from 82 farms across the islands of Trinidad and Tobago. Salmonella was isolated from fresh and frozen samples and the serotype of each was determined through bacterial culture. An in-house, nested PCR that detects all pathogenic Salmonella species was utilized in analyzing the samples. RESULTS: Five samples were positive for Salmonella by bacterial culture, whereas 44 were positive by the nested PCR. Serovars isolated were Kiambu, Orion, Uganda, and two isolates from Group E1 whose H antigens could not be fully characterized. Of the samples, 87 (79 percent) gave equivalent PCR results for both enrichment broths-28 were positive for both and 59 were negative for both). However, 16 samples were positive for one broth, but not for the other, with the majority (14 of the 16) resulting positive for Selenite broth. PCR results for seven samples were inconclusive due to ambiguous band size or multiple bands near the expected band size. CONCLUSIONS: In Trinidad and Tobago, the Muscovy duck does not appear to be a significant source of S. typhimurium or S. enteritidis, but it does harbor other Salmonella species. In-house, nested PCR represents a simple, relatively inexpensive and potentially more sensitive method than bacterial culture for the routine surveillance of pathogenic Salmonella in the Muscovy duck.

OBJETIVOS: Investigar la presencia de Salmonella en patos criollos (Cairina moschata) criados en Trinidad y Tobago e identificar los serotipos circulantes en el país, así como comparar los beneficios relativos del cultivo bacteriano con respecto a la reacción en cadena de la polimerasa (RCP) en la detección y la vigilancia cotidianas de la Salmonella en estos patos. MÉTODOS: Entre marzo y septiembre de 2003 se tomaron 110 muestras de heces fecales de 82 granjas distribuidas por las islas de Trinidad y Tobago. Se aisló Salmonella de muestras frescas y congeladas y se determinaron los serotipos mediante el cultivo bacteriano. Se utilizó un sistema autóctono de RCP anidada que detecta todas las especies patógenas de Salmonella en las muestras. RESULTADOS: Cinco muestras resultaron positivas para Salmonella mediante el cultivo bacteriano, mientras que 44 fueron positivas mediante la RCP anidada. Se asilaron los serotipos Kiambu, Orion, Uganda y dos aislamientos del grupo E1, cuyos antígenos H no se pudieron caracterizar totalmente. Hubo coincidencia en 87 (79 por ciento) de las muestras analizadas por RCP en ambos caldos de enriquecimiento (28 positivas y 59 negativas). Sin embargo, 16 muestras positivas en un caldo resultaron negativas en el otro; la mayoría de ellas (14 de 16) resultaron positivas en caldo selenito. Siete muestras resultaron indefinidas mediante la RCP debido a tallas ambiguas de las bandas o a múltiples bandas cerca de la talla esperada. CONCLUSIONES: El pato criollo no parece ser una fuente importante de infección por S. typhimurium y S. enteritidis en Trinidad y Tobago, aunque hospeda otras especies de Salmonella. El sistema autóctono de RCP anidada constituye un método simple, relativamente económico y posiblemente más sensible que el cultivo bacteriano en la vigilancia cotidiana de especies patógenas de Salmonella en el pato criollo.

Detection of Campylobacter in duck using standard culture method and multiplex polymerase chain reaction.

In 2005, total of 140 samples of duck meat and intestine from slaughterhouses in Nakhon Pathom Province, Thailand, were analyzed for Campylobacter spp. Twenty-eight samples (20%) were positive for Campylobacter spp using the standard culture method (SCM) with 21 samples of C. jejuni and the other 7 C. coli. Forty-four samples (31%) were positive using multiplex polymerase chain reaction, with 34 samples of C. jejuni and 10 of C. coli. This is the first report of Campylobacter contamination in duck in Thailand.

presence of some micro organisms in birds meat. The presence of Yersinia enterocolitica in fresh and frozen birds meat from local supermarkets

A total of 129 meat product samples of frozen and fresh birds [ducks and chicken] entire and section, were collected from several local supermarkets in Hessen [Germany] and tested for the presence of Yersinia enterocolitica and other Yersinia species. The analytical method prescribed from food and drugs administration was validated and performed after few modifications. In the present study, we have followed the cold enrichment method using alkaline treatment and isolating in two selective fluid broth mediums and two selective solid broth mediums. Overall, Yersinia organisms were found on 6 of 67 fresh ducks samples, all of them below to the biogroup 1 A and the serotype o:5 and were nonpathogen [39]. Also Yersinia enterocolitica was found on 6 of 34 fresh chicken samples and all of them were nonpathogen from the same bio and serotype. Other side, all frozen samples were negative. The positive samples were distributed in thighs of chicken and ducks who included skin and this result accord to previous studies. The presence of Yersinia in raw chicken and duck meats represents a health risk for consumers, where further clinical studies are needed to assess the epidemiological importance of this pathogen

Dot blot hybridization assay for the detection of duck hepatitis B virus DNA among healthy Indian country ducks.

A DNA molecular hybridization technique employing Duck Hepatitis B Virus (DHBV) DNA of 3.0 kilobase pairs as a probe was used to screen for the presence of DHBV DNA in blood samples, collected from 90 apparently healthy Indian country ducks. Six out of 90 ducks showed positivity for DHBV DNA in serum (5.4%) and only 4 out of 6 DHBV DNA positive ducks answered in Counter Immuno Electrophoresis (CIEP) using specific antibody against DHBV surface antigen raised in Guinea pig. The results indicate the pilot observation that (a) DHBV carrier status exists to a tune of 5.4% among apparently healthy Indian country ducks also and (b) DHBV probe can be employed as a sensitive and reliable assay for DHBV DNA detection in DHBV infected ducks.