| Congresso Brasileiro de Microbiologia 2023 | Resumo: 521-1 | ||||
Resumo:Frog farming is currently undergoing continuous development and holds significant potential for expanding animal production chains, particularly through the implementation of cooperatives and integrated production systems. However, one of the major concerns in frog meat production is the animals' propensity to act as reservoirs for various pathogens, such as Salmonella spp. This poses a significant risk for the occurrence of foodborne diseases, thereby impacting both food safety and public health. Hence, the objective of this study was to determine the Multilocus Sequence Typing (MLST) profiles of Salmonella isolates obtained from bullfrog carcasses (Lithobates catesbeianus) and the rearing environment in a production system in the state of Minas Gerais, Brazil. A total of 8 Salmonella isolates were selected, comprising 6 samples from bullfrog carcasses and 2 samples from breeding tanks. The isolation of Salmonella spp. was conducted following internationally recognized identification standards (ISO 6579). Genomic DNA extraction was performed using magnetic beads, and Real-Time PCR (qPCR) was employed for molecular confirmation of Salmonella, targeting the invA gene. In order to ascertain the allelic profiles, conventional PCR was conducted on the samples using specific primers for seven conserved housekeeping genes (aroC, dnaN, hemD, hisD, purE, sucA, and thrA). The resulting amplicons were subjected to Sanger sequencing using the BigDye Terminator v3.1 kit (Applied Biosystems) and the ABI 3500 Genetic Analyzer. The FASTA sequences were then uploaded to the public molecular typing databases PubMLST and Enterobase for allelic profile identification. The results revealed the identification of three distinct profiles, namely ST 32, ST 641, and ST 6855, which corresponded to Salmonella Infantis, Salmonella Newport, and Salmonella enterica subsp. enterica serovar 6,8:i:-, respectively. ST 32 and 641 were identified in carcass samples, while serovars 641 and 6855 were found in environmental samples. Notably, the presence of the same ST (ST 641) was identified in both a carcass sample and a breeding tank sample. Furthermore, these identified STs have been previously associated with human salmonellosis, raising concerns regarding public health implications. In conclusion, this study provides significant insights into the presence of Salmonella contamination in both frog carcasses and the rearing environment. The findings underscore the importance of enhancing monitoring and control measures for foodborne microorganisms within the frog farming industry, aiming to improve food safety standards and safeguard public health. Palavras-chave: Bullfrogs, MLST, Salmonella typification, Food safety, Health Public | |||||