Infectio (Dec 2008)
Determinación de Salmonella spp. por PCR en tiempo real y método convencional en canales de bovinos y en alimentos de la vía pública de Montería, Córdoba Detection of Salmonella spp. by real time PCR and standard methods in cattle carcasses and public fast food outlets in Montería, Córdoba
Abstract
Objetivo. Detectar Salmonella spp. por PCR en tiempo real (PCR-TR) y el método convencional en alimentos de la vía pública y canales de bovino de una planta certificada de beneficio animal con sistema HACCP de Montería. Materiales y métodos. Se analizaron 311 muestras de alimentos: 256 de la vía pública y 55 de una planta de beneficio animal. Los análisis microbiológicos se realizaron por el método estándar convencional y la PCR-TR con LightCycler® foodproof Salmonella detection kit (Roche Diagnostics). Resultados. Se aisló Salmonella spp. en 16,1% de las muestras. La prueba de χ²mostró significancia estadística entre las técnicas (pObjective: To establish Salmonella spp. by real-time PCR (RT-PCR) and standard microbiological method in public fastfood outlets and cattle carcasses from a profit animal plant (PBA-slaughterhouse) certified with the HACCP system in the city of Montería. Materials and methods: 311 food samples were analyzed: 256 from public fastfood outlets and 55 from a PBA (slaughterhouse). The microbiological tests were conducted by the standard method, the molecular detection RTPCR was carried out by LightCycler® foodproof Salmonella detection kit (Roche Diagnostics). Results: Salmonella spp. was isolated in 16.1% of the samples. The χ2 test showed statistical significance between techniques (p<0.001), with RT-PCR was obtained by 68% of positive cases and 48% with the conventional method. The fastfood sold in public streets had higher contamination by Salmonella spp. SausageS had Salmonella in 28.1% of the samples by RT-PCR and 12.3% by the conventional method; cheese, 18.4% by RT-PCR, and 5.3% by the conventional method: pork meat, 23.1% by RT-PCR, and 15.4% by the conventional method, and ground meat, 9.3% by RT-PCR, and 15.6% by the conventional method. Cattle carcasses showed a 1.8% of Salmonella spp., a significant difference was observed with respect to spent time for each technique, RT-PCR yielded results within 24 hours as compared to four days for the conventional method. Conclusions: The study showed that RTPCR is a valuable alternative to determine Salmonella spp. in foods for their specificity and promptness, furthermore, the high presence of Salmonella in public fastfood outlets is a public health problem for consumers.
