Prevalence of Salmonella enterica serovars and genovars from chicken carcasses in slaughterhouses in Spain

Aims: To determine the prevalence of Salmonella enterica serovars in chicken carcasses in slaughterhouses in Spain and to examine genotypic relations among these serovars. Methods and Results: A total of 336 chicken carcasses were collected from six slaughterhouses in Northwestern Spain. Salmonellae were isolated ( ISO- 6579- 1993), serotyped, phage- typed, ribotyped and antibiotyped against 20 antibiotics. Salmonella strains were detected in 60 ( 17 center dot 9%) carcasses. Isolates belonged to nine different serotypes, with Salm. Enteritidis being the most common. Three strains ( 5%) were resistant to one antibiotic and 24 ( 40%) were multi- resistant ( to more than one antibiotic). The most frequently encountered resistances were to sulphamides, fluoroquinolones and tetracycline. Ribotyping was able to differentiate isolates of the same serotype and phage type. Conclusions: The Salmonella serotypes and phage types detected are among those most frequently associated with human diseases in Spain. The large percentage of antimicrobial resistant strains is a matter for concern. A high genetic relationship between strains from different slaughterhouses was found. Significance and Impact of the Study: This study provides detailed information about Salmonella isolates from poultry in Spain. It emphasizes the importance of controlling this pathogen in poultry products, and suggests the need for more prudent use of antibiotics.