Genetic characterization of alloherpesvirus (cyprinid herpesvirus-2 and koi herpesvirus) and poxvirus (carp edema virus) identified from domestic and imported cyprinids in Korea

Abstract

Cyprinids are popular species for aquaculture worldwide, with Asia being a significant contributor to their production. In Korea, common carp (Cyprinus carpio), koi carp (Cyprinus rubrofuscus), and goldfish (Carassius auratus) are cultivated domestically and imported for ornamental or human consumption purposes. Among the viruses that infect cyprinids, cyprinid herpesvirus-2 (CyHV-2), koi herpesvirus (KHV, also known as cyprinid herpesvirus-3), and carp edema virus (CEV) are of particular concern as they cause substantial economic losses to the aquaculture industry. In this study, we investigated these viruses in both of domestic and imported cyprinids. Our results revealed that CyHV-2 was only detected in imported goldfish from Thailand. To further investigate the genetic characteristics of them, the marker A region was analyzed. Despite belonging to the same cluster with isolates from China, France, Poland, and Israel, CyHV-2 detected in this study showed distinct differences in their repetitive sequence sizes. Furthermore, two different forms of KHV/CEV coinfection were identified from domestic koi carp, both of which exhibited typical symptoms. Phylogenetic analysis showed that one KHV isolate (ScKc-2105-K) was of the Asian type and closely related to isolates from Japan, Indonesia, Belgium, Taiwan, and China. Two CEV isolates (ScKc-2105-CE and GhKc-2207-CE) belonged to the IIa type and showed high similarity with isolates from the USA, France, and Korea. Notably, koi carp injected with cultured KHV (ScKc-2105-K) showed 78.0% cumulative mortality within 14 days post-injection (dpi). Our findings support the importance of regular surveillance of viral diseases in cyprinids.

Species diversity and conservation status of ornamental fish traded in Kupang, East Nusa Tenggara, Indonesia

“…Cyprinidae is a freshwater fish family with the highest species diversity, morphological and behavioral properties, and habitat requirements (Bain 2011); this family is crucial in the fishery industry in Asian countries (Jeong et al 2023), including Indonesia are 1,790 species recorded in this family (Fricke et al 2023), and 135 of these are found in Indonesia (Froese and Pauly 2023). The large number of Cyprinidae species makes this species potentially important as a food source for the community and ornamental fish trade (Samitra et al 2019).…”