Original Scientific Article
Distribution and genotyping of infectious hematopoietic necrosis virus in farmed rainbow trout and autochthonous salmonids in North Macedonia
Aleksandar Traјchovski * ,
Igor Djadjovski ,
Kiril Krstevski ,
Zagorka Popova-Hristovska ,
Martin Nikolovski ,
Ljubica Rashikj ,
Dimitar Bozinovski ,
Angela Grujovska ,
Niccolò Vendramin ,
Argelia Cuenca ,
Aleksandar Cvetkovikj

Mac Vet Rev 2024; 47 (1): 37 - 43


Received: 18 December 2023

Received in revised form: 29 January 2024

Accepted: 06 February 2024

Available Online First: 13 February 2024

Published on: 15 March 2024

Correspondence: Aleksandar Traјchovski, aleksandar.trajchovski@fvm.ukim.edu.mk


Infectious hematopoietic necrosis (IHN) is a common disease in the intensive production of salmonids. The IHN virus (IHNV) was isolated for the first time in North Macedonia in 2018. This study aimed to investigate the distribution and genotype of IHN in farmed rainbow trout and autochthonous salmonid fish in North Macedonia following the first detection. The samples were collected from 47 trout farms. Trout fry with or without clinical signs of IHN were selected as individual samples. Kidney, spleen, and heart were taken from each fish during the dissection. Three pooled samples were collected from each farm. A total of 141 pooled samples were collected: Rainbow trout (Oncorhynchus mykiss) n=127, Macedonian trout (Salmo macedonicus) n=11, and Ohrid trout (Salmo letnica) n=3. The virus was detected in 43 samples (30.50%): rainbow trout (n=40), Macedonian trout (n=2), and Ohrid trout (n=1). There were 18 (38.30%) positive fish farms. The MAKIHNV1 isolate from 2018 (MN641902) and the newly isolated virus shared a similarity of >99 and were placed in clade E-1 of European genogroup E. The IHN has spread throughout the country and is also present in the autochthonous salmonids.

Keywords: Novirhabdovirus, cold-water aquaculture, phylogeny


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© 2024 Trajchovski A. This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Conflict of Interest Statement

The authors declared that they have no potential lict of interest with respect to the authorship and/or publication of this article.

Citation Information

Macedonian Veterinary Review. Volume 47, Issue 1, Pages 37-43, e-ISSN 1857-7415, p-ISSN 1409-7621, DOI: 10.2478/macvetrev-2024-0013