Parasitic caligid copepods of farmed marine fishes in the Philippines

Recently, heavy infestation of caligid copepods occurred among farmed rabbitfish Siganus guttatus, pompano Trachinotus blochii and sea bass Lates calcarifer in the Philippines. In S. guttatus broodstock, Caligus epidemicus, Pseudocaligus uniartus and Lepeophtheirus sigani concurrently caused severe erosion and hemorrhaging of the body surface, fins and eyes of affected fish occurring at 95.78%, 1.52% and 0.70% of the parasite load, respectively, and with associated mortality of the host fish. In marketable-sized T. blochii, L. spinifer caused body lesions that considerably reduced the market value of harvested fish. In L. calcarifer juveniles, infestation with C. epidemicus resulted to loss of appetite, lethargy and stunted growth of affected fish. Because of its pathogenicity, low host specificity and tolerance to brackish water, C. epidemicus poses the highest threat to farmed marine fish in the Philippines. Lates calcarifer and T. blochii are new host records for C. epidemicus and L. spinifer, respectively. This is also the first record of L. spinifer in the Philippines.This study was funded by the Asia CORE Program of the Japan Society for the Promotion of Science (JSPS). Part of this study was done using the facilities of SEAFDEC Aquaculture Department (AQD) in Iloilo, Philippines. We also thank J.B. Gonzaga and E. Coniza of SEAFDEC-AQD and J. Nealaga of Santeh Feeds Corporation for providing the fish samples and Mila Castaños for editing an earlier draft of the manuscript