Métodos de análise e mapeamento de micro-organismos patogênicos e indicadores de qualidade e higiene na criação e no abate de frangos

Abstract

The aims of this work were to compare different sampling protocols to detect Salmonella and to enumerate quality and hygiene indicator microorganisms in broiler carcasses based on recommendations by legislations in Brazil, European Union and USA, to map the microorganisms present in the main stages of poultry slaughtering, to evaluate the microbiological implications of fecal contamination in poultry carcasses and procedures for removal of this contamination and to compare four techniques for Salmonella identification. In the evaluation of the official procedures from Brazil, European Union and USA the three protocols were equivalent in the detection of Salmonella in broiler carcasses. However, the USA protocol found larger amounts of E. coli, total coliforms, and Enterobacteriaceae than the others but similar counts of aerobic mesophilic. The mapping of the critical stages of slaughter showed that Campylobacter jejuni, C. coli and C. lari were not found in any samples analyzed but Salmonella was detected in random phases of the slaughter process. Scalding reduced contamination of carcasses and cooling in water increased positivity. The presence of Salmonella on farms before slaughter was not related with its presence in the intestine of animals and in the carcasses during slaughter, even in samples contaminated by feces. On the other hand, the prevalence of Campylobacter in carcasses with fecal contamination was high and it was associated with its contamination on the farms and in the intestines of the birds. Washing with water to remove fecal contamination on the carcasses was efficient and decreased the levels of microorganisms indicators of quality and hygiene when compared with trimming. The comparison of techniques to identify the types of Salmonella showed that biochemical VITEK 2TM was efficient to identify S. Enteritidis, but not the other types of Salmonella when compared with serological ones. Ribotyping showed 100% correlation with the serological technique and had the best discriminatory power to identify and differentiate Salmonella isolates. Mass spectrometry identified the isolates only at genus levels and more studies need to be done to improve the application of this technique proves to identify types of Salmonella.