Sea lice (Copepoda: Caligidae) and its Implications in Aquaculture

Abstract

Sea lice including Caligus and Lepeophtheirus (Crustacea, Copepoda, Caligidae) are considered as serious pathogens of cultured fish, causing diseases and economic losses in fish aquaculture worldwide (Rosenberg, 2008). In Korea, some of the important cultured/farmed fishes are infected with pathogenic sea lice, but studies are scanty. Tongyeong marine living resources research & conservation center (TMRC), KIOST, the ranched marine fishes have recently been screened to study the infection of sea lice and its ecology.Identified sea lice are Caligus sclerotinosus Roubal, Armitage & Rohde, 1983 and Lepeophtheirus elegans Gusev, 1951. Here, we report the infection of both sea lice, ecology and its possible life cycle. (1) Caligus sclerotinosus was found infected on the body surface of P. major (Sparidae). Prevalence was 100%, mean and maximum intensites were 7.06 and 49, respectively. Adult females, males and few chalimi were observed and identified by their morphology. As an average of all our collections, less than 0.6% of individuals were chalimi. We suggest, therefore, that adults of C. sclerotinosus undergo ontogenetic host switching after their final moult (Venmathi Maran et al. 2012) (2) Lepeophtheirus elegans was found infected on the body surface and fins of S. schlegelii (Sebastidae). Prevalence was 98.8%, mean and maximum intensities were 6.45 and 29, respectively. Some hosts were found with lesions and severe infection of L. elegans and C. sclerotinosus may cause secondary infection on its host (Venmathi Maran et al. 2013). There have been no reports on sea lice infection from farmed red seabream and Korean rockfish and hence, it is a first report on the infection of C. sclerotinosus in Korea and a new host record for L. elegans (Venmathi Maran et al. 2012, 2013).fected on the body surface of P. major (Sparidae). Prevalence was 100%, mean and maximum intensites were 7.06 and 49, respectively. Adult females, males and few chalimi were observed and identified by their morphology. As an average of all our collections, less than 0.6% of individuals were chalimi. We suggest, therefore, that adults of C. sclerotinosus undergo ontogenetic host switching after their final moult (Venmathi Maran et al. 2012) (2) Lepeophtheirus elegans was found infected on the body surface and fins of S. schlegelii (Sebastidae). Prevalence was 98.8%, mean and maximum intensities were 6.45 and 29, respectively. Some hosts were found with lesions and severe infection of L. elegans and C. sclerotinosus may cause secondary infection on its host (Venmathi Maran et al. 2013). There have been no reports on sea lice infection from farmed red seabream and Korean rockfish and hence, it is a first report on the infection of C. sclerotinosus in Korea and a new host record for L. elegans (Venmathi Maran et al. 2012, 2013).