• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.742-750
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• 2022

This study aimed to monitor the distribution of Cobitidae in Korea by the identification of species using genetic analysis. Based on the genetic analysis, Cobitidae species in four of five domestic fish farms consisted of only Chinese muddy loach Misgurnus mizolepis, but muddy loach Misgurnus anguillicaudatus was also present it in one fish farm. In the case of imported Cobitidae species, in addition to Chinese muddy loach and muddy loach, the harmful species Paramisgurnus dabryanus, was also present. Chinese muddy loach accounted for 20%, 67%, and 60% of the S6, S7, and S8 samples, respectively. An analysis of the total length, body length, and weight showed that domestic Chinese muddy loach showed higher values than imported muddy loach, and imported Chinese muddy loach showed similar values to P. dabryanus. There were no significant differences in the country of origin of the three species. Thus, the mitochondrial cytochrome c oxidase subunit I gene sequence was analyzed and compared the verification of species identification. The three species of Cobitidae were genetically divided into three groups and determined to have genetic differences. These results indicate that it is necessary to reduce the heterogeneous mixing rate through discriminating species by genetic analysis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.265-271
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• 1994

Differences in carotenoid composition in the integuments of wild and cultured chinese muddy loach Misgurnus mizolepis and muddy loach Misgurnus anguillicaudatus were compared. Total carotenoid contents in the integuments of the wild and cultured chinese muddy loach were $4.76mg\%\;and\;3.43mg\%$, respectively. The important carotenoids in the integuments of the wild chinese muddy loach were lutein($30.5\%$), ${\beta}$-cryptoxanthin($24.6\%$), ${\beta}$-carotene($20.6\%$) and cynthiaxanthin($11.7\%$). In addition, zeaxanthin($4.7\%$), tunaxanthin ($4.5\%$), and a-cryptoxanthin($1.0\%$) were present in small amounts. In the integuments of the cultured chinese muddy loach, lutein($35.4\%$), ${\beta}$-cryptoxanthin($17.9\%$), cynthiaxanthin($16.0\%$) and ${\beta}$-carotene($12.7\%$) were present as important carotenoids. In addition, zeaxanthin($8.1\%$), tunaxanthin($5.0\%$), a-cryptoxanthin($0.9\%$) were found in small amounts. Total carotenoid contents in the integuments of the wild and cultured muddy loach were $4.00mg\%\;and\;2.99mg\%$, respectively. The important carotenoids in the integuments of the wild muddy loach were lutein($32.9\%$), ${\beta}$-cryptoxanthin($18.8\%$), cynthiaxanthin($17.0\%$) and ${\beta}$-carotene($15.1\%$). In addition, zeaxanthin($6.5\%$), tunaxanthin($6.0\%$) and a-cryptoxanthin($1.5\%$) were found in small amounts. In the integuments of the cultured muddy loach, lutein($51.8\%$), cynthiaxanthin($19.9\%$) and ${\beta}$-cryptoxanthin($10.8\%$) were observed as important carotenoids. In addition, ${\beta}$-carotene($5.0\%$), zeaxanthin($4.8\%$), tunaxanthin($4.5\%$) and a-cryptoxanthin($0.2\%$) were found in small amounts.

• Journal of fish pathology
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• v.24 no.2
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• pp.167-171
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• 2011

On September in 2010, myxosporidian parasites were found on the fins of Chinese muddy loach, Misgurnus mizolepis, Several cysts of approximately 2 mm diameter were observed on the fins. Numerous spores were found in the cyst. The total length of the spore was 13.0 to 15.8 ${\mu}m$, and the width of spore was 6.0 to 7.5 ${\mu}m$. As the results, the myxosporidians were finally identified as Thelohanellus misgurni (Kudo, 1919) on the basis of the presence of characteristic cysts and size of spores.

• Korean Journal of Ichthyology
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• v.32 no.4
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• pp.232-238
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• 2020

The objective of the present study was to investigate fish farm and growth performances of Chinese muddy loach (Misgurnus mizolepis) under indoor and outdoor aquaculture conditions for the domestic loach aquaculture industry. The investigation was conducted from August 2017 to October 2019 at one indoor farm (D-site) and two outdoor farms (P1-site and P2-site). Results showed that WG (weight gain), DWG (daily weight gain), and SWG (specific weight gain) based on growth measurements were 175.27±36.2%, 7.98±3.3%, and 0.94±0.2% at D-site, 320±34%, 4.07±0.6%, and 0.55±0.1% at P1-site, and 295.9±53%, 4.15±0.5%, and 0.62±0.1% at P2-site, respectively. WG was higher in outdoor farms (P1-site and P2-site), while DWG and SWG were higher in the indoor farm (D-site). Such differences of the present study might be due to differences in growth, water quality, plant and sale frequency depending on aquaculture types. In particular, outdoor farms takes more than a year to have sales whereas indoor farms can have sales three times in a year.