• Journal of Microbiology and Biotechnology
• /
• v.28 no.6
• /
• pp.946-956
• /
• 2018

The gut microbiota of aquatic animals plays a crucial role in host health through nutrient acquisition and outcompetition of pathogens. In this study, on the basis of the high-throughput sequencing of 16S rRNA gene amplicons, we examined the bacterial communities in the gut of freshwater shrimp (Macrobrachium nipponense) and in their living environments (sediment and pond water) and analyzed the effects of abiotic and biotic factors on the shrimp gut bacterial communities. High bacterial heterogeneity was observed in the freshwater shrimp gut samples, and the result indicated that both the surrounding bacterial community and water quality factors (particularly dissolved oxygen and temperature) could affect the shrimp gut bacterial community. Despite the observed heterogeneity, 57 genera, constituting 38-99% of the total genera in each of the 40 shrimp gut samples, were identified as the main bacterial population in the gut of M. nipponense. In addition, a high diversity and abundance of lactic acid bacteria (26 genera), which could play significant roles in the digestion process in shrimp, were observed in the shrimp gut samples. Overall, this study provides insights into the gut bacterial communities of freshwater shrimp and basic information for shrimp farming regarding the application of probiotics and disease prevention.

• Journal of Species Research
• /
• v.5 no.3
• /
• pp.459-462
• /
• 2016

The branchiobdellidan species Holtodrilus truncatus (Liang, 1963) is reported for the first time in Korea. The genus Holtodrilus Gelder and Brinkhurst, 1990 is monotypic within the family Xironodrilidae, and the genus and family of this species are also new to the Korean fauna. The branchiobdellidan specimens were collected from the exoskeletons of the freshwater atyid shrimp, Neocaridina sp., sampled from the 'Andeok Valley', Jeju-do Province, South Korea. Holtodrilus truncatus is characterized by its terete body form, 7/7 dental formula (with a large medial tooth and three pairs of smaller lateral teeth), and no trunk appendages. In addition, we determined a partial sequence of the mitochondrial cytochrome c oxidase subunit 1 (CO1) gene as a DNA barcode marker for H. truncatus. The present study is the first record of the branchiobdellidan occurrence on a non-crayfish host (shrimp) in Korea. To date, seven species (four genera in three families) of branchiobdellidans have been reported in the Korean fauna.

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2001.05a
• /
• pp.524-525
• /
• 2001

White spot syndrome virus (WSSV) causes the most serious epizootic in cultured penaeid shrimp. The epizootic started in 1992, and spread through east and south east Asia and into other shrrimp growing countries of the region. In order to circumvent the epizootic, in many Asian countries, freshwater prawn, Macrobrachium rosenbergii is being widely considered as an alternative species to marine shrimp. (omitted)

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2001.10a
• /
• pp.313-314
• /
• 2001

The palaemonid shrimp Exopazaemon modestus inhabits the freshwater of the Indo-West Pacific, Siberia, Manchuira, Korea, China, Taiwan (Holthuis, 1980) and is abundant in the fresh water areas of southwest of Korea. Palaemonid shrimps are adapted to a variety of habitats in freshwater, brackish and marine environments. They play important role in the ecosystem of fresh, brackish and marine waters, acting as predators feeding on algae, detritus, crustaceans and meiofauna (Bell and Coull, 1978) and in turn, as preys for fishes and other predators (Anderson, 1985). (omitted)

• Journal of Life Science
• /
• v.8 no.5
• /
• pp.550-556
• /
• 1998

In order'to reduce loss of shrimp productivity by viral diseases on the cultured shrimp, we were develope the effective shrimp virus control system. Virus is inactivated by above 5 ppm of chloride and treatment of 50% fresh water. Mortality of infected shrimp is decreased by feeding of immunostimulants such as peptidoglycan and schizophyllan. Mg(OH)$_2$ was one of improvement agents which have best effect on pH, ignition loss(IL), chemical oxidation demand(COD) and total sulfide of water and sediment of shrimp farm.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.39 no.spc1
• /
• pp.198-202
• /
• 2006

We investigated the fecundity, egg size, reproductive output, and breeding frequency and season of Neocaridina denticulata denticulata and Latreutes planirostris which inhabit extremely different habitats. The marine shrimp Latreutes planirostris produced more eggs had at a given carapace length than the freshwater shrimp N. d. denticulata. However, N. d. denticulata had a larger egg volume and greater reproductive output than L. planirostris. The monthly gonadosomatic index (GSI) of the freshwater shrimp began to increase in April and reached a maximum in May, suggesting a single breeding period. In contrast, the GSI of the marine shrimp exhibited two breeding peaks: May-June and September. In both shrimps, the regressions between carapace length and ovarian weight were significant at the non-eyed and eyed embryo stages. For both species, an analysis of covariance revealed significant difference between the two regressions in elevation, but not in slope. These results indicate the potential for multiple ovulations within the reproductive season.

• Animal Systematics, Evolution and Diversity
• /
• no.spc9
• /
• pp.37-44
• /
• 2016

We surveyed the freshwater invertebrates of Jindo Island twice on July and September 2016, as part of a joint faunal survey conducted to commemorate the 30th anniversary of the Korean Society of Systematic Zoology. Aquatic insects were not included in this study. We found 38 freshwater species from seven phyla: Porifera, Platyhelminthes, Nematomorpha, Mollusca, Annelida, Arthropoda, and Bryozoa. Twenty-one of the 38 species (55.3%) represented the first record of their respective species on Jindo Island. Among these species, a freshwater shrimp-parasitic isopod, Tachaea n. sp., was identified as a new species.

• Environmental Analysis Health and Toxicology
• /
• v.25 no.3
• /
• pp.223-228
• /
• 2010

Neocaridina denticulata is a small freshwater shrimp indigenous to Korea. As an indigenous species has long-adapted to particular water environments, the species can be a suitable indicator to assess environmental risks caused by hazard chemicals in the particular site. Thus Neocaridina denticulata, a small freshwater shrimp indigenous to Korea, is worth considering for a test species for such purpose. N. denticulata were exposed to pentachlorophenol sodium salt, sodium azide and potassium dichromate using automatic flow-through system for 96 hours. The 96 hr lethal concentrations ($LC_{50}$) of these chemicals were calculated as $0.53{\pm}0.09\;mg/L$, $2.40{\pm}0.61\;mg/L$ and $1.21{\pm}0.09\;mg/L$ respectively and showed relatively small deviation from repetitive test results. When compared with the toxicity values of other species for each chemical, N. denticulata had moderate or high sensitivity to the toxicity of these chemicals. It can be concluded that N. denticulata is a good test species to evaluate acute toxicity of various hazardous chemicals.

• The Korean Journal of Ecology
• /
• v.15 no.3
• /
• pp.257-265
• /
• 1992

The effects of insecticide dimilin including the technical grade(tg) and wettable power(wp-25), inhibiting the synthesis of chitin in the cuticle of insect larvae, and herbicides alachlor and atrazine on the development of shrimp caridina denticulata denticulata were investigated in various concentrations. This species is abundant in the freshwater such as river and pond. The shrimp larvae were reared at dimilin solutions(tg and wp 2), alachlor solutions, and atrazin solutions. the concentrations of dimiline were 0, 1, 5, 10 and 25 ppb dimilin solutions, and those of alachlor and atrazin were 0, 1, 5, 10 and 25ppm, respectively.mortality was high at 10 ppb when the larvae were exposed to dimilin and at 25ppm in the case of alachlor and atranzine solutions. If lethal concentration is defined as a concentration in which less than 10% of larvae to the post larval stage from hatching it can be concluded that the lethal concentration of dimilin is 5ppb, and that of alachlor and atrazin is 25 ppm.

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2002.05a
• /
• pp.453-454
• /
• 2002