• Ecology and Resilient Infrastructure
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• 제5권4호
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• pp.264-275
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• 2018

The experiment was conducted to investigate the effects of various dietary conditions on external morphometric traits, and sectioned morphometric traits in the cultured cyprinid loach, (Misgurnus anguillicaudatus) for 28 days. For the fed group there was an increase in body weight, standard length, and morphometric dimensions of the head and body cavity regions compared with the starved and initial groups. Sectioned morphometric trait analysis revealed that relative to the starved group, the fed group had greater body circumference, cross-sectional area, and total height (P<0.05). Our results provide data on external and sectioned morphometric changes under starvation conditions, and can be used as a guide to assist in the regulation and scheduling of feeding, and as indices of the nutritional status of cyprinid loach.

• 한국어류학회지
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• 제24권1호
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• pp.1-10
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• 2012

미꾸라지, 미꾸리 및 상반교배를 통해 유도된 종간 잡종의 세포유전학적 분석을 수행하였다. 미꾸라지와 미꾸리의 염색체 수는 각각 2n=48 (12M+4SM+32A), 2n=50 (10M+4SM+36A)이었고, 잡종군들의 염색체수는 각각 2n=49 (11M+4SM+34A)였다. 모든 그룹의 염색체는 동일한 arm number (NF=64)를 갖고 있었으며, 염색체 다형현상, 암수 간 이형의 염색체는 관찰되지 않았다. 적혈구의 크기, DNA 함량을 분석한 결과 잡종군들은 미꾸라지와 미꾸리의 중간 값을 나타냈다. 염색체의 NORs (nucleolar organizing regions)은 모두 동일한 중부염색체 단완부에서 Ag-positive signal이 나타났다. 이상의 결과는 미꾸라지의 1번 중부 염색체와 미꾸리의 차단부 염색체가 Robertsonian 형의 염색체 전좌 과정을 거쳤을 것을 시사한다.

• 한국양식학회지
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• 제10권3호
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• pp.363-371
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• 1997

미꾸리 암컷과 미꾸라지 (Misgurnus mizolepis))$\times$미꾸리(M. anguillicaudatus) 잡종 수컷을 교배시켜 역교배체를 생산하였다. 역교배체의 수정율과 부화율은 친어 수컷으로 사용된 미꾸리와 유사하였다. 더욱이 역교배체는 난황흡수기에 저온에 저항성을 보여 전 실험군이 폐사한 미꾸리군에 비하여 단 14%의 낮은 초기 사망률을 나타내어 뚜렷한 생존율 증가가 관찰되었다. 역교배체의 적혈구 크기와 DNA 함량은 친어 암, 수의 중간을 나타내었고 역교배체는 2n=48 혹은 2n=49인 2가지 종류의 2배체 염색체수를 나타내었다. 부화후부터 6개월 동안 동일 조건에서 성장률을 조사한 결과, 역교배체는 친어 암, 수의 중간 성장을 보여 어류양식시 새로운 양식대상 어종으로의 가능성을 시사하였다. 역교배체는 거의 미꾸리와 체색 및 형태에서 유사하였으나 형질계측결과 친어 암수의 중간을 나타내는 형질 및 몇 개의 새로운 획득형질이 관찰되었다. 역교배체는 부화후 2개월 및 부화후 4개월에서 각기 성비를 조직학적으로 조사한 결과 암컷을 전혀 발견할 수 없어 전 수컷 단성집단 생산의 가능성을 보였다.

• 한국양식학회지
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• 제6권1호
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• pp.55-62
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• 1993

4 배체 미꾸리를 생산하기 위해 수정란에 여러 범위 의 자극 온도와 수정 후로부터 의 경과시간, 그리고 처리 시간에 따라 그 효율을 조사하였다. 4배체 생산에 가장효율이 좋은 조건은 수정 후 28분에 3분간 온도 $41^{\circ}C$에 처리하는 것으로 나타났고, 정상 2배체의 염색체 수가 2n=50으로 나타난 반면 4배체의 염색체 수는 4n=100으로 확인 되었다. 또한 4배체의 적혈구의 용적은 2배체 보다 1.65배나 더 컸으며 4배체와 2배체의 DNA 함량은 각각 6.547 및 3.067pg/cell로 나타났다.

• 한국발생생물학회지:발생과생식
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• 제4권1호
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• pp.19-28
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• 2000

암컷 미꾸라지, Misgurnus mizolepis와 수컷 미꾸리, M. anguillicaudatus간 잡종과 잡종 3배체를 생산하였으며, 잡종화 및 잡종 3배체화가 망막, 시개 및 trunk kidney에 미치는 영향을 조직학적으로 조사하였다. 잡종은 일부 조직의 핵과 세포 크기에서 양친과 거의 유사하였다. 잡종 3배체는 잡종에 비해 적혈구 세포 및 핵 크기, 망막 내과립층 horizontal cell 핵 크기, 망막신경절 신경세포 층의 신경세포, 시개과립층의 신경세포 핵 및 trunk kidney 2차 근위뇨세관 세포 및 핵 크기에서 증가한 반면 망막 외과립층 수와 2차 근위뇨세관 핵 수에서는 감소하였다. 본 연구 결과 잡종에 비해 잡종 3배체의 일부 조직에서 세포 및 핵 크기 증가를 동반한 세포 수 감소 특성은, 미꾸리류에서의 잡종 및 잡종 3배체의 판별 및 배수화 수준 평가의 한 방편으로 사용 가능할 것이다.

• 한국양식학회지
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• 제12권3호
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• pp.167-173
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• 1999

Blocking the 1st mitotic cleavage was performed in mud loach (Misgurmus mizolepis) using UV-irradiated cyprinid loach (M. anguillicaudatus) sperm and ternal shocks Optimum UV range for inactivation of cyprinid loach sperm and thermal shocks. Optimum UV range for inactivation of cyprinid loach sperm was between 3,150 to 4,050 ergs/m$m^2$. Heat shock treatment ($41^{\circ}C$ for 3mins) with various treatment initiation times ranged from 22 to 50 min post insemination resulted wide range of success for induced gynogenesis. Best result was obtained when haploid egges were shocked at 28 min after insemination (corresponding to metaphase division of the 1st cleavage); 26% of total eggs inseminated were viable diploid gynogens. The hatching success and early survival of the both meiotic and mitotic gynogenetic groups were significantly lower than those of control crosses (P<0.05). Maternal origin of induced gynogenetic mud loach was verified by multi-locus DNA fingerprinting.

• 한국발생생물학회지:발생과생식
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• 제17권3호
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• pp.187-198
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• 2013

In this study, we measured the morphometric and histological changes in the cyprinid loach, Misgurnus anguillicaudatus, during the early period of growth. Eyes, yolk length, yolk height, and yolk volume of the larva decreased for 16 days post hatching (DPH) (P<0.05). During 60 DPH (P>0.05), the most anterior extension of the head ${\times}$ the posterior end of the supraoccipital, the most anterior extension of the head ${\times}$ the origin of the dorsal fin, the most anterior extension of the head ${\times}$ the origin of the pectoral fin, the posterior end of the supraoccipital ${\times}$ the origin of the pelvic fin, and the origin of the dorsal fin ${\times}$ the ventral origin of the caudal fin gradually decreased, whereas the most anterior extension of the head ${\times}$ the dorsal origin of the caudal fin, the origin of the dorsal fin ${\times}$ the origin of the anal fin, the origin of the dorsal fin ${\times}$ the origin of the pectoral fin, and the insertion of the dorsal fin ${\times}$ the origin of the pelvic fin gradually increased (P<0.05). In the cyprinid loach, the retina is composed of six layers: the epithelial layer, ganglion cell layer, inner nuclear layer, inner plexiform layer, outer limiting membrane, and rod and cone layer (RCL). After hatching, part of the RCL gradually increased in density. The kidney and midgut epithelium were already formed in the cyprinid loach just after hatching and grew gradually in subsequent days.

• Fisheries and Aquatic Sciences
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• 제4권1호
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• pp.39-46
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• 2001

To examine the effect of copy number-dependent transgenic genotype on the expression of foreign gene, stable hemizygous and homozygous transgenic breeding line was established using artificial parthenogenesis. For this purpose, induced diploid gynogenetic transgenesis was optimized in mud loach (Misgurnus mizolepis) using UV-irradiated cyprinid loach (M. anguillicaudatus) sperm and thermal shocks. Optimum UV range for inactivation of cyprinid loach sperm was between 3,150 to $4,050\;ergs/mm^2$ The UV-irradiated sperm were inseminated into eggs from recessive color strain (yellow) or heterozygous transgenic mud loach containing CAT gene. Cold shock at $2^{\circ}C$ for 60 min, 5 min post fertilization successfully restored the diploidy of eggs inseminated with UV-irradiated sperm. Restoration to diploidy was confirmed by flow cytometry and gynogenetic status was verified by examining maternal exclusive inheritance of multi-locus DNA fingerprints, body color and transgenic marker. Putative isogenic transgenic fish clearly showed homozygous status at trans gene locus based on Southern blot hybridization and progeny testing. Further, such homozygous gynogenetic diploids revealed the increased levels of transgene expression, when compared to those of heterozygous (hemizygous) transgenic fish.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2003년도 추계학술발표대회 논문요약집
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• pp.41-41
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• 2003

Transgenic triploid hybrid between fast-growingtransgenic mud loach (Misgurnus mizolepis) males and cyprinid loach (M. anguillicaudatus) females were generated and their performance on growth, feed conversion ability and reproduction were evaluated. Although the growth accelerations of diploid and triploid transgenic hybrids were not as much as those of original transgenic mud loaches, they still represented persistent growth stimulation ranging 11 to 28 fold when compared to their non-transgenic counterparts, with significantly improved feed conversion efficiency up to 2-fold (compared to non-transgenic hybrid) and 1.5-fold (compared to non-transgenic mud loach) in maximum. The gonad development of diploid hybrids was fertile in histological views regardless of transgenic genotypes but the extent of developmentin hybrid fish were less than mud loach diploids at the same age. On the other hands, very stringent sterility was obtained in both sexes of the triploid hybrid transgenics: ovary and testis from transgenic triploid hybrids were significantly depressed and any notable sign for maturation to ovum or spermatids was not detected. No viable embryo was obtained in a fertilization trial using the suspension prepared from the minced testes of transgenic triploid hybrids. This study may indicate the potential usefulness of triploid hybridization as a mean for reproductive containment of transgenic mud loach.