DAO 110:193-200 (2014)  -  DOI: https://doi.org/10.3354/dao02759

Effects of experimentally induced infections of goldfish Carassius auratus with cyprinid herpesvirus 2 (CyHV-2) at various water temperatures

Takafumi Ito1,*, Yukio Maeno2

1Tamaki Laboratory, Aquatic Animal Health Division, National Research Institute of Aquaculture, Fisheries Research Agency, 224-1 Hiruta, Tamaki, Mie 519-0423, Japan
2Aquatic Animal Health Division, National Research Institute of Aquaculture, Fisheries Research Agency, 422-1 Nakatsuhamaura, Minami-Ise, Mie 516-0193, Japan
*Corresponding author:

ABSTRACT: In this study, we examined the influence of water temperature on the development of herpesviral haematopoietic necrosis (HVHN) in goldfish Carassius auratus after experimentally induced infection with cyprinid herpesvirus 2 (CyHV-2). In Expt 1, Ryukin goldfish were infected with CyHV-2 by intraperitoneal injection and maintained at 4 different water temperatures. Cumulative mortalities of the 15, 20, 25 and 30°C groups were 10, 90, 90 and 60%, respectively. Therefore, the temperature range of 20-25°C is considered highly permissive for HVHN. One of 6 surviving fish of the 15°C group died after a rapid temperature increase to 25°C at 30 d post infection. All 3 Edonishiki goldfish, co-reared with the surviving Ryukin in tanks where the water temperature was increased from 15 to 25°C, died. In Expt 2, Edonishiki goldfish were exposed to CyHV-2 by bath immersion at 13 or 24°C, resulting in cumulative mortalities of 0 and 87%, respectively, at 28 d post-exposure. No mortality of the surviving Edonishiki in the 13°C treatment was observed when the water temperature was increased to 24°C. In addition, in Expt 2, no mortality was observed in any Ranchu co-reared with CyHV-2-immersed Edonishiki in the group where water temperature was increased from 13 to 24°C, even after re-immersion challenge with CyHV-2. It is interesting to note that CyHV-2 DNA was detected in the kidneys of 4 of the 5 surviving Ranchu co-reared with the CyHV-2-immersed Edonishiki group where the water temperature was increased from 13 to 24°C. Therefore, it is likely that the surviving Edonishiki of the 13°C group were virus carriers. This study indicates that most fish infected with CyHV-2 at 13-15°C acquire resistance to HVHN, but as carriers they are able to infect naïve fish.


KEY WORDS: Cyprinid herpesvirus 2 · CyHV-2 · Resistance · Carassius auratus


Full text in pdf format 
Cite this article as: Ito T, Maeno Y (2014) Effects of experimentally induced infections of goldfish Carassius auratus with cyprinid herpesvirus 2 (CyHV-2) at various water temperatures. Dis Aquat Org 110:193-200. https://doi.org/10.3354/dao02759

Export citation
Mail this link - Contents Mailing Lists - RSS
- -