• ALGAE
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• v.26 no.2
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• pp.181-192
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• 2011

Ballasting and deballasting of shipping vessels in foreign ports have been reported worldwide as a vector of introduction of non-native aquatic plants and animals. Recently, attention has turned to ballast water as a factor in the global increase of harmful algal blooms (HABs). Many species of microalgae, including harmful dinoflagellate species, can remain viable for months in dormant benthic stages (cysts) in ballast sediments. Over a period of four years, we surveyed ballast water and sediment of ships docked in two ports of Tampa Bay, Florida, USA. Sampling conditions encountered while sampling ballast water and sediments were vastly different between vessels. Since no single sample collection protocol could be applied, existing methods for sampling ballast were modified and new methods created to reduce time and labor necessary for the collection of high-quality, qualitative samples. Five methods were refined or developed, including one that allowed for a directed intake of water and sediments. From 63 samples, 1,633 dinoflagellate cysts and cyst-like cells were recovered. A native, cyst-forming, harmful dinoflagellate, Alexandrium balechii (Steidinger) F. J. R. Taylor, was collected, isolated, and cultured from the same vessel six months apart, indicating that ships exchanging ballast water in Tampa Bay have the potential to transport HAB species to other ports with similar ecologies, exposing them to non-native, potentially toxic blooms.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.1
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• pp.29-34
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• 2008

The aim of the study was to investigate the effect of dietary fish oil supplementation on the semen characteristics of the Markhoz buck. Sixteen bucks were randomly allocated into 4 groups and received four different diets: unsupplemented control diet, supplemented with fish oil at 2.50% dry matter (DM), supplemented with fish oil (2.50% DM) and vitamin E (0.30 g/kg DM), and supplemented with vitamin E (0.30 g/kg DM). All experimental diets were formulated according to AFRC (1998). Semen was collected at 14 d intervals from June 17, 2006 to September 2, 2006. Semen characteristics were evaluated. Significant effects (p<0.05) of the week (sampling time) were observed for all parameters except semen volume. Also a significant effect (p<0.05) of dietary treatment was observed for all parameters except for percent sperm with normal morphologies and semen volume. Fish oil supplementation with excess vitamin E had a significant effect (p<0.05) on total number and sperm density, motility and progressive motility, percentage viability and dead sperm. The interaction between fish oil feeding and sampling time was significant (p<0.05) for all of the parameters. The bucks that received fish oil in association with vitamin E, effect fish oil showed the greatest improvement in semen characteristics compared with the other groups (p<0.05). This study showed that fish oil supplementation with vitamin E may have a beneficial effect on the semen quality and fertility of Markhoz bucks.

• Parasites, Hosts and Diseases
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• v.50 no.4
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• pp.317-325
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• 2012

The prevalence of foodborne trematode (FBT) metacercariae was investigated in fish from 2 localities of northern Vietnam in 2004-2005. Freshwater fish (9 species) were collected from local markets in Hanoi City (n=76) and Nam Dinh Province (n=79), and were examined for FBT metacercariae using the artificial digestion technique. Adult flukes were obtained from hamsters experimentally infected with the metacercariae at day 8 post-infection. Three (Haplorchis pumilio, Centrocestus formosanus, and Procerovum varium) and 6 (Haplorchis taichui, H. pumilio, C. formosanus, P. varium, Stellantchasmus falcatus, and Heterophyopsis continua) species of FBT metacercariae were detected in the 2 regions, respectively. Overall, among the positive fish species, H. pumilio metacercariae were detected in 104 (80.0%) of 130 fish examined (metacercarial density per infected fish; 64.2). C. formosanus metacercariae were found in 37 (40.2%) of 92 fish (metacercarial density; 14.7). P. varium metacercariae were detected in 19 (63.3%) of 30 fish (Anabas testudineus and Mugil cephalus) (metacercarial density; 247.7). S. falcatus metacercariae were found in all 10 M. cephalus examined (metacercarial density; 84.4). H. continua metacercariae (2 in number) were detected in 1 fish of Coilia lindmani. Morphologic characteristics of the FBT metacercariae and their experimentally obtained adults were described. The results have demonstrated that various FBT species are prevalent in northen parts of Vietnam.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.6 no.1_2
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• pp.1-19
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• 1973

Heavy metal concentrations have been determined in fishes and shellfishes sampled from October 1971 to April 1972 in Korea. In general, fish viscera, shellfish muscle and crustacean exoskeleton contained high concentrations of the metals. With regard to the regional variations of the metals, samples of the west coast of Korea contained relatively high concentrations of mercury, copper, cadmium and lead, but those of the south coast contained high levels of cadmium and lead. In particular, the concentrations of copper in the samples of the west coast were almost twice as much those of the other coasts. The concentrations of mercury in the samples, as a whole, ranged from 0.02 to 0.58 ppm with an average of 0.16 ppm. The concentrations of cadmium were higher in the fish viscera and shellfish than the fish muscle, ranging from less than 0.02 to 0.78 ppm with an average of 0.12 ppm in the fish and shellfish muscle samples. The lead concentrations were slightly high in the fish viscera. In the muscle and bone of fish and shellfish, the range was 0.06-4.84 ppm with an average of about 1 ppm. The concentrations of copper were very high in the viscera of fish and shellfish. The shellfish muscle contained almost four times as much copper as in the fish muscle, particularly cephalopods, i. e., squid and octopus, contained very high levels of copper, and oysters collected from Gunsan area on the west coast contained the highest levels of copper. The concentrations of copper ranged from 0.12 to 28.7 ppm with an average of 1.4 ppm in the fish muscle and of 5.9 ppm in the shellfish muscle.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.842-848
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• 2009

The purpose of this study was to determine the extent of domoic acid (DA) a potent neurotoxin, responsible for the syndrome amnesic shellfish poisoning (ASP) contamination of various species of bivalve shellfish purchased from fish market in Korea and the implications for food safety. Liquid chromatography (LC) methods were applied to quantify DA in shellfish after sample clean-up using solid-phase extraction (SPE) with strong anion exchange (SAX) cartridges. Toxin detection was achieved using photodiode array ultraviolet (LC-UV) and electrospray ionization-mass (LC-ESI-MS). DA was identified in 4 bivalve shellfishes of 872 shellfishes collected from March, 2006 to October, 2007 in Korea. DA amount of 3 surf clams (Mactra veneriformis) collected at Seoul, Daejeon, and Daegu were 4.13, 1.99, and 1.94 mg/kg, respectively. DA amount of 1 pink butterfly shell (Peronidia venulosa) collected at Seoul was 3.02 mg DA/kg. The amounts of DA that were present in 4 bivalve shellfishes were within EU guideline limits for sale of shellfish (20 mg DA/kg).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.1
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• pp.1-7
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• 2009

The toxicity of two species of puffer fish, Takifugu poecilonotus (Heuinjeombok) and T. vermicularis (Gukmaeribok) collected from the coastal regions of Korea was determined using a mouse bioassay. In the T. poecilonotus collected in Jeju and Tongyeong, the proportion of toxic specimens containing ${\ge}10$ mouse units (MU) per gram exceeded 95% for the skin, liver, ovary, and fin, and approximately 30% for the testis and muscles. In each of the organs, the highest toxin levels were 79 MU/g in the muscle, hundreds (158-365) of MU per gram in the fin, intestine, testis, and gallbladder, but thousands (1,147-2,406) of MU per gram in the skin, liver, and ovary. In T. vermicularis collected from Incheon and Gunsan, the proportions of toxic specimens were 100% for the gallbladder, and 56-68% for the skin, fin, liver, and intestine however, no toxic muscle specimens were noted. The highest toxin scores were below 10 mouse units (MU) per gram in the muscle, 20-94 MU/g in the skin and fin, 319 MU/g in the intestine, and thousands (1,548-4,624) of MU per gram in the liver, gonad, and gallbladder. The toxicity in the muscle of T. vermicularis was deemed acceptable for human consumption, whereas the toxicities in the muscle of T. poecilonotus and the skin of both species of puffer fish were significantly high, such that special attention may be required when the fish is intended for human consumption.

• Korean Journal of Ichthyology
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• v.36 no.2
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• pp.174-181
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• 2024

This study examines the community characteristics of fish species collected by fyke net from the eastern coastal waters of Yeosu, Korea, during the period from 2020 to 2021. A total of 4,539 fish were sampled and classified into 43 species, 28 families, and 7 orders. The dominant species included Mugil cephalus (14.4%), Konosirus punctatus (10.9%), Lateolabrax japonicus (8.3%), Acanthopagrus schlegelii (7.9%), and Pennahia argentata (7.2%). The diversity index was highest in October (H'=2.888) and lowest in February (H'=2.075). Furthermore, the dominance index was highest in March (DI=0.524) and lowest in December (DI=0.178). Hierarchical cluster analysis (HCA) revealed that fish communities could be divided into three groups based on Bray-Curtis similarity. Group 1, consisting mainly of species collected from June to October, formed one cluster. Group 2, including winter spawning species such as Pseudopleuronectes yokohamae, Clupea pallasii, and Hexagrammos otakii, sampled from November to February, formed another cluster. Group 3, which included species such as Larimichthys polyactis, Amblychaeturichthys hexanema, and Sebastes inermis, formed a cluster collected from March to May. The eastern coast of Yeosu is considered a suitable habitat for fisheries resources, including highly economically valuable species, and it is also assumed to be an important spawning and nursery ground for many fish species.

• Parasites, Hosts and Diseases
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• v.24 no.1
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• pp.1-11
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• 1986

Larval anisakids found in the yellow corvina (Pseudosciaena manchurica), a marine fish caught in the Yellow Sea, were classified by their morphological types. Total 1, 068 anisakid larvae were collected from 30 fish examined, with the average number per fish of 35.6. They were classified into Anisakis type I larvae of Berland (859 in number, 80.4%), Contracaecum type A of Koyama et at. (13, 1.2%), Contra caecum type C'(new type) (55, 5.1%), Contracaecum type D of Koyama et aZ. (18, 1.7%), Contracaecum type D' (new type) (77, 7.2%), Contracaecum type V of Yamaguti (3, 0.28%), Raphidascaris sp. of Koyama et aZ. (1, 0.09%) and unidentified (42, 3.9%). Contracaecum type C' and D' were considered new in the literature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.983-996
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• 2014

Fish catches by a set net from January 2007 to November 2009 were analyzed to assess fish species composition and seasonal variations in the coast of Gijang, Korea. Over 389 kg fish representing 78 species, 45 families and 17 orders were collected during three years of the study. Dominant species were jack mackerel Trachurus japonicus, anchovy Engraulis japonicus and herring Clupea palasii, and these three species comprised 67.3% of the total number of individuals and 60.7% of the total biomass. Size distribution of the dominant species for jack mackerel, anchovy and herring ranged from 2.2 cm to 22.6 cm, from 2.5 cm to 14.8 cm, from 4.0 cm to 29.0 cm in fork length, respectively. Anchovy was the only species that occurred throughout all seasons in the Gijang coast. Generally, species richness was highest in spring (April to June) when sea temperature began to increase.

• Parasites, Hosts and Diseases
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• v.56 no.5
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• pp.509-513
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• 2018

Present study was performed to survey infection status of digenetic trematode metacercariae in 2 alien fish species, Micropterus salmoides (largemouth bass) and Lepomis macrochirus (bluegill), in 2 rivers draining Chungcheongbuk-do, Republic of Korea. A total of 107 largemouth bass and 244 bluegills were caught in Daecheong-ho (ho=lake) and Musim-cheon (a branch of Geum-gang), in Chungcheongbuk-do April-July 2015. Additionally, 68 native fish of 5 species, i.e., Zacco platypus, Hemibarbus longirostris, Carassius auratus, Pseudogobio esocinus and Puntungia herzi, were caught from the same water bodies. All of the fish collected were examined by artificial digestion method. The metacercariae of Centrocestus armatus, Clinostomum complanatum, Metagonimus sp. and Diplostomum spp. were detected from 4 out of 5 native fish species in Daecheong-ho. However, any metacercariae were not found from 87 M. salmoides and 177 L. macrochirus in Daecheong-ho. In Musim-cheon, metacercariae of Exorchis oviformis and Metacercaria hasegawai were detected from 78% Z. platypus and 34% L. macrochirus, but any metacercariae not found in M. salmoides. We report here that the 2 alien fish species were less infected with the metacercariae than the native ones. Surveys on the metacercariae in the alien fish species in geographically various rivers should be undertaken for better understanding on the role of alien fish species in the trematode infections in Republic of Korea.