• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.2
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• pp.85-89
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• 1997

한국서해안 격열비열도 근해산 문치가자미의 연령과 성장을 조사하기 위하여 1992년 9월부터 1993년 8월까지 매월 정기채집한 256개체의 이석을 연령형질로서 사용하여 조사 분석한 결과를 보면, 이석의 투명대와 불투명대는 년 1회 형성되었으며 투명대 형성시기는 7월이고 불투명대 형성 시기는 2월에서 4월로 이는 산란종기(2월)와 일치함을 보였다. 연령별 체장 (LT)과 연령(t)을 von Bertalanffy 성장식에 적용하여 수컷은 Lt=313.7[1-exp{-0.4342(t+0.9017)}, 암컷은, Lt=458.1[1-exp{-0.2368(t+0.1934)}과 같은 관계식을 구하였다. 또한 암컷과 수컷의 성장속도는 2세까지는 별다른 차이를 보이지 않았으나, 3세어 이상에서는 암컷이 수컷보다 월등히 빠름을 나타내었다. 본 연구에서의 최고령어는 암수 각각 5세와 6세였다.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.23-23
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• 2003

프리마틴(freemartin)이라 함은 반추동물들 중 특히 소에서 나타나는 간성(intersex)형태로 이성 쌍자의 경우 태어난 암컷의 대부분이 정상적인 자성 생식기의 발육 및 발생양상을 지니지 못하여 생식불능상태로 되는 것으로 알려져 있다. 최근 실용화된 수정란이식이나 쌍자유기 등의 기술은 현재 일반 농가에 까지 정책적으로 확대 보급되어 산업화되고 있는 실정이나 불행히도 이러한 기술들을 이용하여 생산된 개체들 중 상당수가 이성쌍자로 이들 중 암컷 개체들은 거의 freemartin으로 생산되어 실지 노력에 비해 경제적 효과들을 크게 반감시키고 있다. 뿐만 아니라 생산된 freemartin 개체들에 대하여 조기 진단 없이 다만 형태적으로 암컷으로 판단하여 번식우로 사양관리 함에 따른 경제적 손실이 매우 크다 할 수 있겠다.

• Korean journal of applied entomology
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• v.31 no.1
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• pp.37-44
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• 1992

Morphometrics of the sensory appendages for host plant discrimination such as antenna, leg, rostrum of S. furcifera sampled from Korea, China, and Philippines were determined and compared. Computed discriminant scores of 89 characters produced scatter diagrams and group centroids revealing discrete segregations of the three populations.

• Korean Aquaculture
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• v.14 no.1
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• pp.63-66
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• 2002

담수산 rotifer, Brachionus calyciflorus는 담수어류의 종묘생산시 초기 자어의 먹이생물로 많이 이용되고 있다. 특히, 이 종의 암컷은 수컷에 관계없이 암컷이 난을 생산하는 처녀생식과 수컷과의 교미에 의해 암컷이 수정란(내구란)을 형성하는 유성생식으로 나뉘어진다. 한편, 유성생식에 의해 형성된 내구란은 두터운 2차 난막으로 싸여져 있어 외부환경이 부화에 적합하지 않으면 강한 내구성을 지니고 있어 휴면 상태를 계속 유지한다. 이러한 내구란은 종의 유전적 형질을 효율적으로 보관할 수 있을 뿐만 아니라 대량배양하기 위한 종자 및 수산 생태 독성학의 실험재료로 이용할 수 있다. 또한 내구란은 Artemia cyst처럼 쉽게 부화시켜 자어에 직접 먹이로 공급할 수 있는 장점으로 인해 rotifer 대량배양에서 오는 유해 세균과 원생동물에 의한 자치어의 2차 감염을 방지 할 수 있다. 이처럼 rotifer, B. calyciflorus 내구란은 여러 가지 용도로 이용 가능하기 때문에 내구란을 대량생산할 수 있는 조건을 규명하는 것도 중요하다. 그리고 생산된 내구란을 사용 목적에 따라서 간편하게 이용하기 위해서는 내구란을 제품으로 만드는 것도 매우 중요하다. 따라서 본 내용은 담수산 rotifer 내구란을 상품화하기 위한 방법으로 내구란의 대량생산과 보존방법에 대해서 설명하고자 한다.

• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.542-549
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• 2014

This study was conducted to investigate the body size, sexual size dimorphism (SSD), and related environmental factors between Red-tongued viper snakes (Gloydius ussuriensis) inhabiting two different places, i.e., Jeju Island and its islet Gapado, and to provide data required to maintain species diversity from May, 2006 until June, 2009. The snout-vent length of the Red-tongued viper snake population inhabiting Jeju Island was found to be 242-532 mm ($422.0{\pm}46.7mm$, n = 100) in females and 296-580 mm ($434.5{\pm}51.7mm$, n = 63) in males. In contrast, the snout-vent length was observed to be 205-395 mm ($335{\pm}43.6mm$, n = 55) in female and 215-430 mm ($328{\pm}39.4mm$, n = 73) in male Red-tongued viper snakes inhabiting Gapado. These data demonstrated the snout-vent length of both female and male Red-tongued viper snakes on Jeju Island to be larger than those on Gapado (Female t = 17.343, df = 115, P<0.001; Male = 19.128, df = 101, P<0.001). SSD was measured to be -0.03 in the Red-tongued viper snake population on Jeju Island, with more or less larger sizes in the males, while it was 0.02 in the Red-tongued viper snake population in the Gapado, with a little larger sizes in the females. The reason for this difference in the snake populations between Jeju Island and Gapado may be due to adaption to the different ecological environments. In addition, as SSD, the snout-vent length of the Red-tongued viper snake populations and in young vipers was somewhat higher in the males than in the females on Jeju Island (t = -2.011, df = 117, P<0.05). However, no significant differences were observed in the snout-vent length of the young and the general Red-tongued viper snake populations on Gapa Island. For the population on Jeju island, the head length (F = 6.318, $df_{1,2}$=1,117, P<0.05), head width (F=8.090, $df_{1,2}$=1,117, P<0.01), inter eye length (F=15.898, $df_{1,2}$=1,117, P<0.001), and tail length (F=238.488, $df_{1,2}$=1,111, P<0.001) were all larger in the males, while females showed higher body mass (F=64.111, $df_{1,2}$=1,114, P<0.001). In the case of the Gapa Island population, no significant differences in the head length, head width, and inter eye length between females and males were observed, while the males had a longer tail length (F=168.555, $df_{1,2}$=1,74, P<0.001) and the females were heavier (F=17.812, $df_{1,2}$=1,76, P<0.001). Though no significant differences were found in the head length, head width, and inter eye length, the tail length (F=67.793, $df_{1,2}$=1,72, P<0.001) and body mass (F=4.558, $df_{1,2}$=1,72, P<0.05) were higher in the young male Red-tongued viper snakes than in the females. The snout-vent length, head length, head width, and inter eye length, which did not display SSD in the young Red-tongued viper snake populations, were higher in the male Red-tongued viper snake populations than in the female population from Jeju Island, implying that SSD in the Red-tongued viper snake population on Jeju Island is expressed due to environmental effects during their growth.

• Journal of Sericultural and Entomological Science
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• v.37 no.1
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• pp.74-85
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• 1995

A study was conducted to provide some basic data for controlling the Mulberry scale insect(Pseudaulacaspis pentagona T.). Experiments were carried out with checking their field-life, and a few selected insecticides were tested when mulberry leaves were not in use. About 57% of female were survived from the overwintering attached to the bark. Over 80% of the scale were distributed within the range of 30cm from the base of each stem. One hundred percent and 96.7% of eggs were hatched under 25$^{\circ}C$ and 27$^{\circ}C$ respectively. Eighty percent of pupae emerged both under 25 and 27$^{\circ}C$. The Mulberry scale require about 33 days under 25$^{\circ}C$ and 30 days under 27$^{\circ}C$. This species had 2 generations each year in mulberry field in Suwon. Overwintered as a mated female only. Oviposited about 170 eggs under their scale starting from the late April (in 1994) through the mid May (in 1993). Phenthoate EC sprayed in the mid June against the larvae was very effect with over 96% of control value.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.77-82
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• 1997

This study was carried out to investigate the developmental characteristics and life cycle of sciarid fly (Lycoriella sp.), an important mushroom pest. The sciarid fly was reared ina growth chamber at 21$\pm$$1^{\circ}C$ and 55$\pm$5% of relative humidity with a 16h high, 8h dark cycle and Flammulina velutipes was used at diet. The egg was oval with 0.17 mm in diameter and 0.27 mm in length. Average egg period was 4 days. Body length of each instar from the 1st to 3rd was 0.7, 1.5, and 4.5, mm. respectively. Average weight of each instar was 1.9, 15.4 and 93.6 $\mu\textrm{g}$, respectively. In the 4th instar larvae, however, developmental characteristics of female and male became different by body length, weight and segment size. Body length and weight of the 4th instar female larvae were 5 mm and 162$\mu\textrm{g}$, and those of the male larvae were 3.5 mm and 90 $\mu\textrm{g}$, respectively. The larval periods of female and male were respectively 13.5 and13 days. Pupal length of female and male was 3.5 and 2.7 mm, and average weight was 136 $\mu\textrm{g}$ and 6.5$\mu\textrm{g}$, respectively. Adults were emerged from female and male pupae on 5.5 and on 5 days after pupation, respectively. Average longevity of male and female were 7 and 5 days, respectively. The weight of female was two-fold heavier than the male. After copulation, female laid approximately 130 to 150 eggs on/in the sporophore of mushroom. In conclusion, total lifespan of male and female were 29 and 28 days, respectively.

• The Korean Journal of Malacology
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• v.32 no.3
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• pp.197-202
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• 2016

This research reports the intersexuality of bivalves, such as Crassostrea gigas, Mytilus galloprovincialis, Rupiditapes philippinarum, Gomphina veneriformis and Barnea davidi discovered during the process of investigating the ecological health status of coastal waters of Korea. In intersex ovaries, the opposite germ cells were observed either individually or in groups in the interfollicular space and inside the oogenic follicle. Oocytes in the intersex testis were at the previtellogenic or initial vitellogenic stage. They were either scattered individually or in groups in the interfollicular space and inside the spermatogenic follicle. The intersexuality in C. gigas was 10.4% (n = 19/183), while female (12.2%, n = 6/49) exhibited a higher proportion than male (9.7%, n = 13/134). The intersexuality in M. galloprovincialis was 31.7% (n = 19/60), while female (36.4%, n = 12/33) exhibited a higher proportion than male (25.9%, n = 7/27). The intersexuality in R. philippinarum was 11.2% (n = 11/98), while male (16.7%, n = 7/42) exhibited a higher proportion than female (7.1%, n = 4/56). The intersexuality in G. veneriformis was 28% (n=30/107), while male (31.5%, n=17/54) exhibited a higher proportion than female (24.5%, n=13/53). The intersexuality in B. davidi was 18.4% (n = 7/38), while female (35.7%, n =5 /14) exhibited a higher proportion than male (8.3%, n = 2/24).

• Journal of Aquaculture
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• v.18 no.1
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• pp.52-59
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• 2005

The productivity of cyclopoid copepod, Apocyclops royi fed by various diets (Isochrysis galbana, Tetraselmis suecica, Phaeodactylum tricornutum, concentrated freshwater Chlorella and baker's yeast) was investigated at tile different temperatures ($16-36^{\circ}C$) with different salinities (5-34 ppt). A. royi was cultured in 6 ml vessels (12 wells culture plate). Total production (188 inds.) and daily production (13.4 inds.) of nauplii by A. royi female at $32^{\circ}C$ were significantly higher than those of nauplii at the different temperatures (P<0.05). Development time from nauplii to copepodite and from nauplii to adult tended to increase with increasing water temperature up to 32. And total production (169 inds.) and daily production (9 inds.) of nauplii by A. royi female at 10 ppt were significantly higher than those of nauplii at the different salinities (P<0.05). The fastest development time from nauplii to copepodite and from nauplii to adult was observed at 10 ppt and 15 ppt, respectively (P<0.05). The highest total production of A. royi nauplii and fastest development time from nauplii to adult were obtained in females fed Isochrysis galbana (P<0.05). These results may indicate that the optimum culture temperature and salinity for A. royi are $32^{\circ}C$ and 10 ppt, respectively, and Isochrysis galbana is one of the suitable diets for this copepod.

• Biomedical Science Letters
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• v.1 no.1
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• pp.19-25
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• 1995

Characterization of immune cell subpopulations in the bovine was performed using a direct immunofluorescence technique adaptable for routine and repeated monitoring. This whole blood procedure is faster and requires less volume than conventional density gradient isolation methods. Low inter-and intra-animal variations were seen in hematology parameters and in CD4, CD8 and CD2 lymphocyte subtypes. CD4 values were 30% of lymphocytes in male and 32% in females. Thriteen percent were CD8 in males and 13% in females. CD4: CD8 ratios were approximately two in both sexes. Fiffty three percent were CD2 in males and 54% in females. The mean RBC counts of peripheral blood were 7.20$\times10^6/{mm}^3$ for male cattle and 6.36$\times10^6/{mm}^3$ for females. The mean WBC counts were 8.09$\times10^3/{mm}^3$ for males and 7.09$\times10^3/{mm}^3$ for females. The percent of lymphocytes(63-65%) was higher than the percent of neutrophils(17-18%), the percent of eosinophils(11-15%), te percent of monocytes(4-5%), and percent of basophiles(1%).