World Aquaculture Singapore 2022

November 29 - December 2, 2022

Singapore

ADVANCES IN GENOMIC ANALYSIS OF PATHOGENIC Yersinia ruckeri AND Aeromonas sobria ISOLATED OF PERUVIAN RAINBOW TROUT

Fernando Mesías V.*, Luis Llanco, Carmen Hurtado, Tania Rodríguez, Diego Gerpe, Jesús Romalde, and Enrique Serrano-Martínez

 

Laboratorio de Parasitología Veterinaria

Universidad Peruana Cayetano Heredia

Av. Honorio Delgado 430- SMP- Lima- Perú

fernando.mesias@upch.pe

 



Yersinia ruckeri and Aeromonas sobria frequently affect rainbow trout production in Peru, mostly causing haemorrhages in different organs, by expressing virulence factors such as hemolysins, cytotoxins, proteases, among others. Additionally, constant outbreaks of both pathogens in peruvian fish farms could be, despite applying antibiotics for their control, associated with the development of antimicrobial resistance in these pathogens. Although virulence and antimicrobial resistance factors have been investigated in Y. ruckeri and A. sobria in some countries, these studies are scarce in Peru. Therefore, the aim of the present study was to identify genes related to virulence and antimicrobial resistance in Y. ruckeri and A. sobria isolated from rainbow trout (Oncorhynchus mykiss) from Lima, Peru.

Yersinia ruckeri strain FMV-22 and Aeromonas sobria CHT-30 were isolated from diseased rainbow trout raised in Canta- Lima, which presented frequent haemorrhagic septicaemia despite receiving antibiotic treatments. These strains were grown in trypticase soy agar at 25 °C for 24 h, and confirmed by PCR. Genomic DNA of both strains were extracted and then they were sequenced using an Illumina MiSeq sequencer. Both SPAdes and QUAST used default parameters to perform genome assembly and to evaluate the assembly, respectively. The resulting genomes consists of 108 contigs (3 843 148 bp) with G+C content of 47.45% for FMV-22 strain, and 343 contigs (4 912 126 bp) with G+C content of 57.67% for CHT-30 strain. The N50 contig sizes were 152,665 bp for FMV-22 strain, and 151,159 bp for CHT-30. ABRIcate was used to screen antimicrobial resistance and virulence genes (Table 1) in FMV-22 and CHT-30 strains, using CARD, VFDB, ARGANNOT and RESFINDER databases. Our results will contribute to expand our knowledge about the pathogenesis and antimicrobial resistance of both bacteria that significantly affect peruvian rainbow trout production.