Incidencia de Escherichia coli serotipo O157:H7 en carne proveniente de ganado bovino de mataderos de Puerto Rico

The main objective of this investigation was to evaluate the incidence of Escherichia coli O157:H7 in cattle during the slaughter process in Puerto Rico. The slaughter houses visited were located in Mayaguez, Arecibo and Yauco. The current methods of reduction for bacterial counts and the prevention of food borne pathogens were also evaluated. The sampling method used was the one proposed by the Unites States Department of Agriculture (USDA) for processing of samples and the detection of E. coli O157:H7 using the method of polyurethane sponges. The animals sampled for the investigation were classified based on their race and age. The results for the presence of E. coli O157:H7 in the carcass prior and after the wash were negative. The bacterial counts in the samples were not significant throughout the investigation. The statistical analysis used was the MacNemar test. There where no significance differences with the treatment applied to the carcass. The Wilcoxon test analysis was also performed to compare the reduction of bacterial counts in the carcass. These values fluctuated depending on the slaughter house (p<0.05). The results of the serological tests performed indicated the presence of generic E. coli, and a possible Enterobacter aerogenes and Enterobacter cloacae. Based on these results it can be assumed that the slaughter houses visited had Good Manufacturing Practices (GMP's), Standard Sanitization Operational Procedures (SSOP's), Standard Procedures of Sanitization (SPS) and followed their Hazard Analysis and Critical Control Points (HACCP) plans.