Co-existence of two Yersinia ruckeri biotypes and serotype O1a retrieved from rainbow trout (Oncorhynchus mykiss) farmed in Puno, Peru

Carla Fernandez-Espinel, Marco Medina-Morillo, Rute Irgang, Giovanna Sotil, Henry Araya-León, Violeta Flores-Dominick, Jesús L. Romalde, Ruben Avendaño-Herrera, Jefferson Yunis-Aguinaga

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)


Yersinia ruckeri causes important economic losses for rainbow trout (Oncorhynchus mykiss) farms worldwide. This bacterial disease is likely the most common among trout in Peru; however, no commercial vaccine is available nationally, which is, in part, due to a lack of information on the bacterium. The aim of the current study was to characterize 29 Y. ruckeri isolates sampled from seven cage-reared farms in the Puno Region, the focal point for aquaculture activities in Peru. For this, samples were taken from fish with clinical signs (i.e. haemorrhages, uni- or bilateral exophthalmia, hyphaemia and/or melanosis). Notable among our findings was the existence of both Y. ruckeri biotype 1 (9 isolates) and biotype 2 (20 isolates; negative for sorbitol and Tween 80). The isolates further differed in API profiles 5307100 (21 isolates), 1307100 (4 isolates), 1305100 (2 isolates), 1307120 (1 isolate) and 5305100 (1 isolate), with the main differences being in the tests for lysine decarboxylase, gelatine hydrolysis and D-saccharose fermentation. Despite these differences, all isolates shared identical ERIC-PCR and REP-PCR profiles and belonged to the O1a serotype. Fingerprints were identical to the reference strain CECT 955 (serotype O1a). The information obtained will be used for epidemiological purposes by health authorities and for the development of a vaccine against Y. ruckeri, a prominent request made by fish farmers in Peru.

Original languageEnglish
Pages (from-to)157-163
Number of pages7
JournalJournal of Fish Diseases
Issue number2
Publication statusAccepted/In press - 2022


  • biotype 2
  • enteric redmouth disease
  • serotype O1a
  • yersiniosis

ASJC Scopus subject areas

  • Aquatic Science
  • veterinary (miscalleneous)


Dive into the research topics of 'Co-existence of two Yersinia ruckeri biotypes and serotype O1a retrieved from rainbow trout (Oncorhynchus mykiss) farmed in Puno, Peru'. Together they form a unique fingerprint.

Cite this