• 한국양식학회지
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• 제21권1호
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• pp.47-53
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• 2008

본 연구의 목적은 rotifer Brachionus rotundiformis의 영양강화와 자어의 소화기능을 높이기 위해 소화효소 활성이 높은 rotifer의 선택방법을 제시하는 것이다. 소화효소 활성을 측정하는 개체군은 성장과정에 있는 개체군들 중 임의로 표본 수집하여 소화효소활성을 측정하여 결정하였다. 선택된 개체군에서 개체밀도와 성장률의 관계가 RD=5865 SGR-350.08(P<0.001)로 나타났다. 포란률은 성장률과 개체밀도와의 관계가 각각 F=-36.147 SGR+61.652(P<0.05)와 F=-0.0085 RD+66.38(P<0.001)로 나타났다. 성장률과 소화효소 활성의 rotifer 개체당 활성은 Amyl=-1.6482 SGR+3.2498(P<0.05), TAP=-0.8115 SGR+1.1361(P<0.001) 및 TGL+0.0055 SGR+0.0079(P=0.239)로 나타나 TG-lipase 활성에서는 성장률과 관계없는 것으로 나타났다. 또한 포란률과 rotifer 개체당 소화효소 활성의 관계는 Amyl=0.0296 F+1.0981(P<0.001). TAP=0.0252 F+0.0975(P<0.001) 및 TGL=-6E-06 F+0.0113(P=0.915)으로 나타나 TG-lipase 활성이 포란률과 관계없는 것으로 나타났다. 반면 TG-lipase의 단백질 비활성과 포란률, 성장률 및 개체밀도와의 관계는 각각 TGL=-0.0024 F0.2332(P=0.132), TGL=0.1267 SGR+0.005(P<0.01) 및 TGL=0.0002 F-0.0594(P<0.001)로 나타나 TG-lipase 단백질 비활성은 포란률과의 관계를 제외하고 각각 상관된 변화를 보였다. 따라서 rotifer의 영양강화효과와 자어에게 외부기인 소화효소 전달을 위한 높은 소화효소 활성을 보이는 rotifer 개체군이 개체밀도가 높은 개체군보다는 포란률이 높은 경우에 나타났기 때문에 포란률이 높은 개체군을 선택하여 영양강화하고 자어에 공급하는 것이 보다 자어에 유익할 것으로 판단된다.

• 한국응용곤충학회지
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• 제54권2호
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• pp.83-89
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• 2015

Mimosa pudica (미모사), Argemone mexicana (멕시코 가시양귀비) Leucus aspara (꿀풀과 일종), Polygonum hydropiper (여뀌), Blumea lacera (국화과 일종) 등 5종의 식물 헥산추출물들의 팥바구미 성충에 대한 살충, 성충우화억제력 및 녹두 종실피해 방제력이 검증되었다. 그 결과, 밭바구미 성충 살충력은 35-69%이었으며, 녹두에 추출물을 처리한 후 성충우화 방제율은 33-63%, 종실 피해 방제율은 13-49%이었다. 추출물의 농도가 증가할수록 살충력, 성충우화 및 종실피해 방제율 등이 증가하는 것으로 나타났다. 이와 같이 5종의 식물 헥산추출물들은 밭바구미 친환경 방제제로 이용가능성이 있을 것으로 판단된다.

• International Journal of Industrial Entomology and Biomaterials
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• 제18권2호
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• pp.69-75
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• 2009

Daba ecorace of Antheraea mylitta Drury (Lepidoptera: Saturniidae), the semi domesticated Indian tropical tasar silkworm being reared outdoor; the egg and silk yields are dependent of genotype environment interaction. The insufficient maintenance and multiplication of its P4 seed stock need a coherent as well as scientific strategy to safeguard breed potential, being commercially applied ecorace. The sort-out lines of P4 stock studied over five generations highlighting on commercial trait up gradation suits for a tropical crop season, revealed enhanced performance. The line with high pupal parents (T2) shown improved fecundity (12.9%) and the line with high shell parents (T3) recorded higher shell weight (40.0%) and silk ratio (24.1%). While, the line of high pupal female and high shell male (T4) reveal enhancement in fecundity (9.0%), egg hatching (14.1%), shell weight (50.0%), silk ratio (35.2%) and absolute silk yield (52.0%) indicating the need and role of varied basic seed stock lines. The approach could improve economically vital egg fecundity and cocoon shell weights besides balancing them in same line for commercial operation. The progressive show of lines (T1 to T4) along successive generations (G1 to G5), in spite of passing through seed crop (Jul-Aug) and commercial crop (Sep-Nov) seasons emphasize their compatibility. The study infers that the strategic plan of combining preferred parental phenotypes, methodical selection for desired commercial trait(s) through generations with best possible genotype environment interaction has enriched P4 stock with elevation in needy trait(s) besides assuring choice of suitable lines for seasons and regions and timely replenishment of basic seed of Daba ecorace.

• Environmental Analysis Health and Toxicology
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• 제22권2호통권57호
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• pp.157-163
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• 2007

Tetrabromobisphenol A (TBBPA) is the most widely used BFR (brominated flame retardants) as a reactive flame retardant in printed circuit boards, and as additive applications in several types of polymers. The purpose of this study is to assess the adverse effects of TBBPA on the benthic amphipod (Hyalella azteca). Results on the acute toxicity of TBBPA using Hyalella azteca showed that NOEC and LOEC are 100mg/kg and 200mg/kg, respectively. In addition, when chronic toxicity of TBBPA was investigated at the concentration ranges between 0.01 to 100mg/kg, it was found that NOECs are $10mg/kg(fecundity){\sim}100mg/kg(viability)$, respectively. Significant fecundity inhibition was appeared at 100mg/kg of TBBPA, however, this concentration did not show severe adverse effect on weight increment. The values of PNEC were determined as 0.1mg/kg (fecundity) and 1mg/kg (lethal effect), respectively, using a safety factor suggested by EU and OECD.

• Environmental Analysis Health and Toxicology
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• 제25권2호
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• pp.153-159
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• 2010

Perfluorooctane sulfonic acid (PFOS) and Perfluorooctanoic acid (PFOA) are the principal chemicals known as perfluoroalkyl acids (PFAs). Despite the widespread use of these compounds, relatively little is known about their fate and effects. The purpose of this study was to determine the toxic effects of PFOS and PFOA on Daphnia magna. In the acute toxicity test, D. magna were exposed for 48 hours at concentrations of 0, 30, 45, 67.5, 101.25 and 151.88 mg/L PFOS, and 0, 100, 160, 225, 337.5 and 506.25 mg/L PFOA, respectively. In the case of chronic toxicity test, D. magna were exposed through water for 21 days at concentrations of 0, 0.375, 0.75, 1.5, 3 and 6 mg/L PFOS, and 0, 1.25, 2.5, 5, 10 and 20 mg/L PFOA, respectively. Acute toxicity was assessed on the basis of immobility, while chronic toxicity was assessed on the basis of fecundity. The acute toxicity test on PFOS and PFOA showed that the values of $EC_{50}$ were 50.90 mg/L and 253.47 mg/L, respectively. In the chronic test, fecundity was reduced significantly at 1.5 mg/L of PFOS and 10 mg/L of PFOA, respectively. These results indicated that PFOS is more toxic to zooplankton than PFOA, and both chemicals have some hazard demonstrates risk for acute or chronic toxicity to freshwater organism.

• 한국수산과학회지
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• 제39권4호
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• pp.349-356
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• 2006

Gonad development in the sandfish Arctoscopus japonicus was investigated using a histological method. Specimens were collected monthly from April 2003 to March 2004, in the East Sea of Korea. The gonadosomatic index (GSI) of females began to increase in August, reached a maximum in November, and declined sharply in December. By contrast, in males, the GSI began to increase in June and reached a maximum in August. The annual reproductive cycle of A. japonicus can be divided into four successive stages in females: the early growing (January-March), late growing (April-August), ripe and spent (September-November), and recovery (December) stages. Males passed through early growing (January-April), late growing (May-July), ripe and spent (August-November), and recovery (November-December) stages. These results indicate that the spawning season was from October to December. The egg diameter of mature oocytes was 3.12$\pm$0.02 mm. The relationship between fecundity (F$_e$) and body length (BL) was F$_e$=0.4693BL$^{2.6825}$. Fecundity ranged from 483-2,254 eggs in a body length of 14.3-22.9 cm and increased with body length. The body length at 50% maturity was 14.80 cm, which corresponded to an age of 2.40 years.

• 한국수산과학회지
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• 제47권3호
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• pp.255-263
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• 2014

We investigated the reproductive characteristics of Lycodes tanakae in the coastal waters of the middle East Sea to elucidate the species' population structure. We investigated Lycodes tanakae maturation and spawning based on samples collected by Danish seine and gill nets from January 2012 to December 2013. We analyzed monthly changes in maturity stage, gonadosomatic index (GSI), egg diameter, fecundity, and total length at 50% group maturity. The spawning period was December to February, while fecundity ranged from 1,677 eggs at 57.3 cm (total length;TL) to 6,445 eggs at 75.7 cm. The relationship between TL and fecundity (F) was $F_e=6E-05TL^{3.127}$ ($R^2$ = 0.516), and F increased with increasing TL. We estimated the TL at 50% group maturity as 60.4 cm for females and 59.8 cm for males. This study is the first report of Lycodes tanakae reproductive characteristics in the coastal waters of the middle East Sea.

• Clinical and Experimental Reproductive Medicine
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• 제41권2호
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• pp.75-79
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• 2014

Objective: To study the effect of body composition on reproduction in women with unexplained infertility treated with a controlled ovarian hyperstimulation and intrauterine insemination programme. Methods: This prospective observational study was conducted on 308 unexplained infertile women who were scheduled for a controlled ovarian hyperstimulation and intrauterine insemination programme and were grouped as pregnant and non-pregnant. Anthropometric measurements were performed using TANITA-420MA before the treatment cycle. Body composition was determined using a bioelectrical impedance analysis system. Results: Body fat mass was significantly lower in pregnant women than in non-pregnant women ($15.61{\pm}3.65$ vs. $18.78{\pm}5.97$, respectively) (p=0.01). In a multiple regression analysis, body fat mass proved to have a stronger association with fecundity than the percentage of body fat, body mass index, or the waist/hip ratio (standardized regression coefficient${\geq}0.277$, t-value ${\geq}2.537$; p<0.05). The cut-off value of fat mass, which was evaluated using the receiver operating characteristics curve, was 16.65 with a sensitivity of 61.8% and a specificity of 70.2%. Below this cut-off value, the odds of the pregnancy occurrence was found to be 2.5 times more likely. Conclusion: Body fat mass can be predictive for pregnancy in patients with unexplained infertility scheduled for a controlled ovarian hyperstimulation and intrauterine insemination programme.

• 한국응용곤충학회지
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• 제34권1호
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• pp.65-69
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• 1995

파굴파리의 발육단계별 특성을 조사한 결고, 20, 25, $30^{\circ}C$에서 난기간은 4.5일, 2.9일, 1.9일, 유충기간은 12.7일, 5.8일, 4.5일, 용기간은 20.1일, 16.3일, 13.0이로 총성숙기간은 32.5일, 25.0일, 19.4일이었다. 이 결과는 토대로 계산된 발육영점온도는 난이 $13.0^{\circ}C$, 유충이 $11.0^{\circ}C$, 용은 $7.2^{\circ}C$였고, 유효적산온도는 난이 33.0일도, 유충이 86.1일도, 용이 293.6일도였다. 성충은 빛을 조사한 후 4시간 30분 이내에 77.5%가 우화하였고, 8시간 30분 이후에는 전혀 우화하지 않았다. 암컷의 수명은 8.5일, 수컷은 5.0일이었고 암컷의 산란기간은 6.8일이었다. 산란수는 165.8개, 흡즙혼수는 983.8개였다.

• 한국어류학회지
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• 제27권3호
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• pp.217-227
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• 2015

미끈망둑의 생식생태와 개체군 동태를 조사하였다. GSI값은 3월부터 5월까지 높게 나타났다. 포란수는 3.1~4.0 cm (SL)에서 241개, 5.1~5.7 cm (SL)에서 716개의 범위를 보였다. 체장과 포란수의 관계식은 $F=11.242SL^{2.464}$ ($R^2=0.65$)이고, 포란수는 크기와 함께 증가하였다. 50% 군성숙체장은 2.6 cm로 나타났다. 산란기는 4~5월이었다. 성장 매개변수의 추정은 von Bertalanffy growth function (VBGF) 모델을 이용하였다 ($L_{\infty}=63.00mm$ TL, $K=0.85yr^{-1}$). 가입유형은 1년에 1회로 나타났다. 성장 비교지수 (${\phi}$)는 3.53으로 나타났다. 자연사망계수 (M)는 $1.00yr^{-1}$로 추정되었다.