• Smart Media Journal
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• v.12 no.3
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• pp.112-119
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• 2023

Shrimp farming has been becoming a new source of income for fishermen in South Korea. It is often necessary for fishers to measure the size of the shrimp for the purpose to understand the growth rate of the shrimp and to determine the amount of food put into the breeding pond. Traditional methods rely on humans, which has huge time and labor costs. This paper proposes a deep learning-based method for calculating the size of shrimps automatically. Firstly, we use fine-tuning techniques to update the Mask RCNN model with our farm data, enabling it to segment shrimps and generate shrimp masks. We then use skeletonizing method and maximum inscribed circle to calculate the length and width of shrimp, respectively. Our method is simple yet effective, and most importantly, it requires a small hardware resource and is easy to deploy to shrimp farms.

• Animal Systematics, Evolution and Diversity
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• v.22 no.1
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• pp.51-55
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• 2006

Two caridean shrimps, Eualus biunguis (Rathbun, 1902) and Argis toyamaensis (Yokoya, 1933), collected from the Korean continental slope of the East Sea at depths of 850-870 m are reported as new to the Korean caridean fauna with brief descriptions and illustrations. A hippolytid shrimp, E. biunguis, is distinguished from the congeners by the minute che1alike appearance of dactyli of the last three pereopods and the large pyriform eye. A crangonid shrimp, A. toyamaensis, differs from the Korean species of the genus in having the posterior acute spines of submedian carinae on the sixth abdominal somite.

• Animal Systematics, Evolution and Diversity
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• v.39 no.4
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• pp.314-318
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• 2023

The genus Athanas is a member of alpheid shrimps living in temperate and tropical waters worldwide. Species of the genus Athanas are small and inhabit coral reefs, rock or muddy bottoms. As a result of continuous taxonomic research on shrimps collected from Korean waters, Athanas parvus is newly added to Korean fauna through the description of adult form. Athanas parvus is distinguished from A. japonicus by the biunguiculated dactyli of third, fourth and fifth pereopods and spines on ischium of first pereopod. The Korean Alpheidae fauna now consists of nine genera and 27 species including two species of the genus Athanas.

• Proceedings of the Korean Society of Life Science Conference
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• 2005.04a
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• pp.166-167
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• 2005

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1998.06a
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• pp.302.1-302
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• 1998

• Korean Journal of Ichthyology
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• v.17 no.4
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• pp.258-263
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• 2005

Feeding habits of Hapalogenys mucronatus (10.1~22.1 cm) collected from coastal waters off Sori Island, Yeosu, from June 2003 to May 2004 were studied. H. mucronatus is a carnivore which consumes mainly caridean shrimp, crabs, polychaetes, and amphipods. Its diet includes small quantities of bivalves, cephalopods, seagrass, hermit crabs, isopods, eggs, mysids, gastropods, and copepods. H. mucronatus undergoes significant size-related changes; smaller fish (10~11.9 cm) prey mainly on amphipods, shrimps and bivalves, while the proportion of caridean shrimp increases with fish size (12~17.9 cm). The larger fishes (18~22.1 cm) eat caridean shrimps and polychaetes.

• Journal of fish pathology
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• v.14 no.1
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• pp.16-20
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• 2001

The pathogenicity of the extracted WSBV from the hepatopancreas, the lymphoid organ, the stomach and the heart of infected shrimps was examined after artificial infection in shrimps(Penaeus chinensis). In terms of the infection route, the strength of the pathogenicity of WSBV was in the order of intramuscular, oral and dipping method. The influence of rearing water temperature on the pathogenicity of WSBV was the strongest in the order of $30^{\circ}C$, $25^{\circ}C$, $20^{\circ}C$, and $15^{\circ}C$. The isolated WSBV from the diseased shrimps showed very high pathogenicity regardless of their sizes, even though there was difference in time to reach 100% mortality. Degenerated cells characterized by hypertrophied nuclei were found in various tissues such as the lymphoid organ, the hematopoietic tissue and the epidermis in the stomach.

• Journal of Aquaculture
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• v.15 no.1
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• pp.7-13
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• 2002

Since 1993, the White Spot Syndrome Virus (WSSV) disease occurred in China among cultured shrimps resulting in mass mortality. Epizootiological surveys undertaken during the outbreak period of 1993-1994 indicated that all stages of Penaeus chinensis, P. japonicus and P. monodon were infected. Consequent to the transport of contaminated shrimp seedlings and seawater, the disease spread all over the farms of China. The disease was more rapidly transmitted at temperatures above $25^{\circ}C$. Challenge experiments showed the causative agent was highly virulent. White spots appeared on the carapace of both span-taneous and experimentally infected shrimps. Moribund shrimps contained turbid hemolymph, hypertrophied Iymphoid organ and a necrotic mid-gut gland. Electron microscopy showed the presence of viral particles in the gills, stomach, lymphoid organ, and epidermal tissue of the infected shrimp. The visions were slightly ovoid with an envelope and averaged 350 $\times$ 150 nm; nucleocapsids measured 375 $\times$ 157 nm. With discontinuous sucrose gradient of 35, 50 and 60% (w/v), the virus was separated from hemolymph of the infected shrimp. The estimated molecular weight of genomic DNA was 237 Kb with EcoR I, 247 Kb with Hind III and 241kb with Pst I. A total of 9 hybridoma colones secreting monoclonal antibodies (MAbs) were produced from mouse myeloma and spleen cells immunized with WSSV. The immunofluorescence assay of gill tissue showed that the MAbs reacted with diseased but not with healthy shrimp. The MAbs belonged to IgGl, IgG2b subclass and IgM class, all with kappa light Immune-electron-microscopy with colloidal gold marker showed the presence of 5 MAbs epitopes on the envelope and one on the capsid of the virus. Baculoviral mid-gut gland necrosis showed the specificity of the MAbs produced. For diagnosis 5 different methods were selected. Using Kimura primers for PCR, or MAbs for immunoblot, ELISA or FAT method, in situ hybridization was carried out to show the gene. All these methods detected WSSV in the organ samples of the diseased shrimp but not in healthy one.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.4
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• pp.465-469
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• 1993

This study was designed to investigate fatty acid composition of salt-fermented seafoods in Chonnam area. The seven samples were analyzed for fatty acid composition. The contents of lipid was highest in salt-fer-mented anchovies and followed by salt-fermented small mullets, salt-fermented oysters, salt-fermented sea-arrows and salt-fermented small shrimps. The ratio of fatty acid composition depended on the samples but the major fatty acids were $C_{l6:0}$, $C_{20:5}$, $C_{l6:1}$, $C_{22:6}$, and $C_{l8:1}$ among all samples. The composition of n-3 polyunsaturated fatty acids was highest in salt-fermented sea-arrows (39.11%) and followed by salt-fermented small shrimps, salt-fermented oysters, salt-fermented anchovies and salt-fermented small mullets. In n-3 polyunsaturated fatty acids, $C_{20:5}$ was relatively abundant in salt-fermented oysters (17.71%) and salt-fermented sea-arrows (16.38%), and $C_{22:6}$ in salt-fermented sea-arrows (22.22%) and salt-fermented small shrimps (15.13~21.50%). However, $C_{22:6}$ was very little in salt-fermented small mullets.l mullets.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.532-542
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• 1997

Seasonal variation of a shrimp community in the eelgrass (Zostera marina) bed in Kwangyang Bay, Korea was studied based on the monthly collected samples through a year of 1994. The shrimp community in the eelgrassbed was composed of 26 species of shrimps representing 6 families. The community was dominated by Heptacarpus pandaloides, Crangon affinis, Eualus leptognathus, Latreutes acicularis, Heptacarpus rectirostris, Heptacarpus geniculatus, and Latreutes laminirostris. Most of species were the small-sized species with carapace length smaller than 25 mm. The peak abundance occurred in the late winter and spring and low abundances in autumn. More than 10 species were collected every month except lull (8 species). Species diversity indices showed that the shrimp species were more diverse during the late summer, and lesser during the late autumn. Predominance of Crangon affinis in the late autumn caused such a low diversity. The shrimps in the study area could be grouped into three groups on the basis of their occurrence patterns: resident species, seasonal species, and temporary species. More abundant and more diverse shrimps were collected during nighttime than daytime.