Detection of a new strain of lymphocystis disease virus (LCDV) in captive-bred clownfish Amphiprion percula in South Sulawesi, Indonesia

Abstract

Breeding of ornamental marine fishes was initiated in Makassar, South Sulawesi, Indonesia, to protect reef ecosystems from destructive fishing and to supplement income of local communities. However, stress associated with captive breeding conditions could enhance vulnerability of fish to disease. Wild-and captive-bred clownfish Amphiprion percula showed clinical signs such as white spots and warts typically associated with lymphocystis disease. Sequencing a portion of the DNA polymerase gene confirmed the identity of a lymphocystis disease virus (LCDV) in clownfish tissues that closely resembled LCDV from paradisefish; however, both strains were only 90% similar at the nucleotide level. Phylogenetic analysis suggests the LCDV is a new strain representing the first sequence of LCDV in A. percula. To determine the virus presence in clownfish and other ornamental marine species (OMS) in the hatchery, we developed conventional PCR and loop-mediated isothermal amplification (LAMP) assays that were comparatively sensitive at detecting the new LCDV strain. Among the PCR-tested clownfish, 19.4% (n = 14/72) were positive for the LCDV DNA that were either symptomatic or apparently healthy. Other OMS (n = 29) bred in the hatchery including seahorse Hippocampus spp., mandarin fish Synchiropus spp., and pajama cardinal fish Sphaeremia nepatoptera were negative by the LCDV PCR. The PCR and LAMP assays developed in this study will facilitate disease management by early detection of the LCDV and removal of potential reservoirs of the virus.

DETECTION AND GENOTYPE DETERMINATION OF LYMPHOCYSTIS DISEASE VIRUS FROM ORANGE CLOWNFISH Amphiprion percula IN BATAM

“…The fully developed warts on the body surface were present in the caudal peduncle and abdomen (Figure 1). This clinical sign was similar to the white wart on the dorsal fins of LCDV-infected clownfish A. percula in Makassar (Lam et al, 2020). In this study, the lesions in the mouth were found in one fish (data not shown).…”

“…Lymphocystis disease virus (LCDV) is the causative agent of lymphocystis disease, affecting more than 140 species of marine and freshwater fish worldwide, both wild and farmed fish. The pathognomonic signs of lymphocystis-infected fish are mostly external multinodular tumor-like or wart-like masses growths on the fins, skin, or gills (Hick et al, 2016;Lam et al, 2020). Nodular lesions may also be observed on the surfaces of viscera.…”

“…The densities A. ocellaris are significantly lower in coral reefs with high exploitation than in reefs with low exploitation (Madduppa et al, 2014). A study by Lam et al (2020) has confirmed the lymphocystis disease virus from the captive-bred clownfish Amphiprion percula from South Sulawesi by sequencing a portion of the DNA polymerase (DNAPol) gene. Breeding efforts of the orange clownfish A. percula, has been conducted at Batam Mariculture Development Center.…”

Peripheral Blood B-Lymphocytes Are Involved in Lymphocystis Disease Virus Infection in Flounder (Paralichthys olivaceus) via Cellular Receptor-Mediated Mechanism

“…Lymphocystis disease virus (LCDV), a member of the genus lymphocystivirus within the Iridoviridae family [ 1 , 2 ], is the etiological agent of lymphocystis disease. Lymphocystis disease is a well-known disease that is characterized by the presence of pearl-like nodules on the skin, fins and internal organs of the fish [ 3 ], which has affected more than 140 marine, brackish and freshwater fish worldwide [ 4 ], and new LCDV isolations are still continuously found in wild and cultured fish species [ 5 , 6 , 7 ]. The incidence rate of this disease may reach 70%, causing significant economic losses for the aquaculture industry [ 8 ].…”

Sea anemones in the marine aquarium trade: Market preferences indicate opportunities for mariculture and conservation

“…Anemonefish are among the most commonly captivebred ornamental marine fish (Pouil et al, 2020). Successful anemonefish mariculture occurs commercially in countries including Indonesia (Sinansari & Priono, 2019;Lam et al, 2020), indicating a shift from wild harvest to mariculture. Ideally, both the anemones and anemonefish should be sustainably captive bred for the marine aquarium trade.…”