A Novel Fish Pathogen in Rainbow Trout (Oncorhynchus mykiss, Walbaum): Pseudomonas edaphica of Outbreak in Türkiye

Kan Ş., Kubilay A., Önalan Ş.

AQUACULTURE RESEARCH, cilt.1, sa.1, ss.1-15, 2025 (SCI-Expanded)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 1 Sayı: 1
  • Basım Tarihi: 2025
  • Dergi Adı: AQUACULTURE RESEARCH
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aquatic Science & Fisheries Abstracts (ASFA), Artic & Antarctic Regions, BIOSIS, CAB Abstracts, Environment Index, Food Science & Technology Abstracts, Geobase, INSPEC, Pollution Abstracts, Veterinary Science Database
  • Sayfa Sayıları: ss.1-15
  • Van Yüzüncü Yıl Üniversitesi Adresli: Evet

Özet

This study was conducted to identify the disease that caused 30-40% mortality in a rainbow trout (Oncorhynchus mykiss) farm in July 2023. In examinations of infected rainbow trout showed darkening color, bilateral exophthalmos, dropsy, splenomegaly, melting in the liver and kidney, bleeding in the organs were observed. The bacteria was isolated from the anterior kidney and liver of infected fish. It was identified as Pseudomonas edaphica by physical, biochemical and 16S rRNA analysis methods. According to the results of the antibiogram test, the P. edaphica pathogen was resistant to most antibiotics. The antibiotic to which the isolate most sensitive was norfloxacin. In addition, we designed a challenge test to evaluate virulence of the pathogen on rainbow trout. The agent was re-isolated from the liver and kidney in the challenge test. The mortality of the group infected with 10⁷ CFU/ml P. edaphica solution was calculated as 60%, and that of the group infected with 108 CFU/ml P. edaphica solution was calculated as 80%. This study is the first report on the isolation of P. edaphica from rainbow trout and its virulence. It has not been reported before as a pathogen in fish. This study showed that it is a novel pathogen in rainbow trout.