Investigation of microbial communities across swine slaughter stages and disinfection efficacy assessment in a pig slaughterhouse

The processing environment of pig slaughterhouses is a significant potential source of bacterial contamination in pork products for sale. In this study, we employed 16S rRNA sequencing and diversity analysis to characterize the heterogeneity of microbiota on carcass surfaces and environment of a swine slaughterhouse. Furthermore, we assess variations in microbiota across swine slaughter stages, as well as the effectiveness of disinfection by analysing microbial diversity before and after disinfection. The results indicated that the predominant genus present in all samples were Psychrobacter spp., followed by Acinetobacter spp. The occurrence of cross-contamination within the slaughterhouse is prevalent, particularly during interactions involving fresh pig carcasses, including worker operations, tools, and machinery. Remarkably, trimming emerges as a critical control point and a pivotal factor in cross-contamination. The disinfection procedure were partly effective in reducing of microbial contamination of the environment, significantly reducing bacterial diversity and favoring some genera such as Psychrobacter and Weissella confusa. This study provides a deeper understanding of microbial contamination in abattoirs and emphasizes the importance of disinfection. Moreover, it offers scientific suggestions for implementing effective disinfection.