Investigation of the presence of nervous necrosis virus (NNV) in pikeperch (Sander lucioperca) and crayfish (Pontastacus leptodactylus)

Hakan Eren; Sibel Yavru

doi:10.12714/egejfas.43.1.01

TR EN

Sudak (Sander lucioperca) ve kerevitte (Pontastacus leptodactylus) nervöz nekrozis virüsünün (NNV) varlığının araştırılması

Öz

Bu çalışmada, göçmen kuşlar için önemli durak noktaları olan Eğirdir, Beyşehir ve Suğla göllerinde yaşayan sudak (Sander lucioperca) ve kerevitlerden (Pontastacus leptodactylus) NNV varlığı araştırılmıştır. 2022 yılında Eğirdir, Beyşehir ve Suğla göllerinden 3 farklı su sıcaklığı döneminde (15-20°C, 20-25°C ve 25-30°C) kerevit ve sudak örnekleri alınmıştır. Toplam 540 örnek (270 sudak ve kerevit) gerçek zamanlı RT-PCR ile NNV genomunun (RNA-1 ve RNA2) varlığı açısından analiz edilmiş ve ayrıca E-11 hücresine inokule edilmiştir. Hiçbir teknikle pozitif örnek kaydedilmemiştir. Bu çalışmada, Türkiye'nin tatlı sularında yaşayan yabani sucul organizmalarda NNV'nin varlığı ilk kez araştırılmış ve örneklenen sudak ve kerevitlerde NNV tespit edilmemiştir. Çalışmanın yapıldığı tarihte virusa rastlanılmamış olsada, göçmen kuşların göç yolları üzerinde bulunan bu göllerin NNV açısından düzenli olarak incelenmesinin önemli olduğu düşünülmektedir.

Anahtar Kelimeler

Investigation of the presence of nervous necrosis virus (NNV) in pikeperch (Sander lucioperca) and crayfish (Pontastacus leptodactylus)

Abstract

In this study, samples were taken from pikeperch (Sander lucioperca) and crayfish (Pontastacus leptodactylus) living in Eğirdir, Beyşehir, and Suğla lakes, which are key stopovers for migratory birds. In 2022, crayfish and pikeperch were sampled from Eğirdir, Beyşehir and Suğla lakes at 3 different water temperature periods (15-20°C, 20-25°C and 25-30°C). A total of 540 samples (270 pikeperch and crayfish) were analyzed for the presence of NNV genome (RNA-1 and RNA2) by real-time RT-PCR and also inoculated in E-11 cell. No positive samples were recorded by any of the techniques. In this study, the presence of NNV was investigated for the first time in wild aquatic organisms living in freshwaters of Türkiye and NNV was not detected in the sampled pikeperch and crayfish. However, it is important to regularly examine these lakes, which are located on the migration routes of migratory birds, for NNV.

Keywords

Supporting Institution

This research was supported and funded by the General Directorate of Agricultural Research and Policies (TAGEM), Ministry of Agriculture and Forestry of the Republic of Türkiye, under Project No: TAGEM/HSGYAD/B/22/A5/P4/5421. The study is also derived from the doctoral dissertation submitted by Hakan Eren to the Institute of Health Sciences, Selçuk University.

Project Number

Project No: TAGEM/HSGYAD/B/22/A5/P4/5421.

Ethical Statement

This study was conducted in accordance with the principles outlined in the Directive of the Animal Experiments Local Ethics Committee of the Eğirdir Fisheries Research Institute Directorate, affiliated with the General Directorate of Agricultural Research and Policies (TAGEM), Ministry of Agriculture and Forestry of the Republic of Türkiye. Ethical approval was granted by the committee on 28 April 2021 (Decision No: 01).

Thanks

I would like to thank Dr. Gülnur Kalaycı, Dr. Tuncay Vural, Dr. Murat Kaplan, Dr. Vedat Yegen, Dr. Kemal Pekmez, Dr. Oğuz Yaşar Uzunmehmetoğlu, İsmail Hakkı Öztuna, and Rahmi Uysal for their valuable help and support during this study. I am also especially grateful to Dr. Isabel Bandín for her scientific advice and guidance.

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Details

Primary Language

English

Subjects

Fish Pests and Diseases

Journal Section

Research Article

Authors

Hakan Eren ^*
0000-0001-8475-4237
Türkiye

Sibel Yavru
0000-0002-5839-364X
Türkiye

Publication Date

February 13, 2026

Submission Date

October 6, 2025

Acceptance Date

November 9, 2025

Published in Issue

Year 2026 Volume: 43 Number: 1

DOI

https://doi.org/10.12714/egejfas.43.1.01

IZ

https://izlik.org/JA33UE33RN

Cite

RIS / Bibtex

APA

Eren, H., & Yavru, S. (2026). Investigation of the presence of nervous necrosis virus (NNV) in pikeperch (Sander lucioperca) and crayfish (Pontastacus leptodactylus). Ege Journal of Fisheries and Aquatic Sciences, 43(1), 1-8. https://doi.org/10.12714/egejfas.43.1.01