• Title/Summary/Keyword: 암수

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A Case Study of Foraging Time Budget and Habitat Selection of Oriental White Storks (Ciconia boyciana) in Natural State (자연상태에서 황새의 섭식 행동과 서식지 선택에 대한 사례연구)

  • Sung, Ha-Cheol;Cheong, Seok-Wan;Kim, Jung-Hee;Kim, Su-Kyung;Park, Shi-Ryong
    • Korean Journal of Environmental Biology
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    • v.26 no.2
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    • pp.121-127
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    • 2008
  • As a step toward developing conservation and restoration plans for an endangered species of the Oriental White Stork (Ciconia boyciana), we studied daily foraging behavior and ecology. We released two individuals, male and female, after enclosing study site with a fence and cutting out a part of two or three feathers of primaries. Research was conducted from 16 June to 11 July, 2007 for 25 days at Whawonri, Mewonmyung, Chungbuk province. We investigated diural and daily variation of foraging time budget, diet composition, and habitat selection of the feeding individuals. The storks quadratically invested for foraging time and resting time according to time of day, but no significant variation in the foraging time and resting time appeared daily over 25 days. As a result, the storks mainly used wetland as a foraging site in the center of the study area to that in the edge as well as to other types of habitat. The high usage for wetland in the center did not change over the 25 days while Rice field decreased and Wetland in the edge and Pathway increased. Female invested more time for foraging than male, but the foraging efficiency did not differ between them. We discussed the significance of foraging behavior and habitat selection for management plan.

Seed Production from Pond Cultured Cherry Salmon, Oncorhynchus masou (Brevoort) (육상수조에서 계대사육한 시마연어, Oncorhynchus masou (Brevoort)의 종묘생산)

  • Seong, Ki-Baik;Kim, Kyung-Sik
    • Journal of Aquaculture
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    • v.20 no.1
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    • pp.14-18
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    • 2007
  • Seed production of the cherry salmon, Oncorhynchus masou (Brevoort) were studied in terms of egg development, hatching rate, juvenile growth, smolt duration, smolt rate, and adult growth rates. Fork length and body weight of $0^+$ juvenile were $9.32{\pm}1.19\;cm$ and $9.36{\pm}3.50\;g$ for females and $9.07{\pm}1.02\;cm$ and $8.57{\pm}3.04\;g$ for males, respectively. Body weights of $1^+$ smolt were $84.09{\pm}18.1\;g$ and $86.33{\pm}41.2\;g$ for females and males, while body weights of $1^+$ parr were $101.88{\pm}60.9\;g$ and $98.38{\pm}39.6\;g$ for females and males, respectively. Monitoring of gonadosomatic index (GSI) confirmed that maturations of both sexes were not synchronous; males achieved highest GSI in September, while females achieved it in October.

Disruption of Sex Differentiation by Exogenous Sex Steroid Hormones in Korean Rockfish, Sebastes schlegeli (외인성 성스테로이드 호르몬에 의한 조피볼락, Sebastes schlegeli의 성분화 교란)

  • Kwon, Joon-Yeong;Lee, Chan-Hee;Kim, Ju-Yeong;Kim, Sang-Hun;Kim, Dae-Jung;Han, Hyoung-Kyun;Lim, Han-Kyu;Byun, Sun-Gyu
    • Development and Reproduction
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    • v.10 no.4
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    • pp.247-254
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    • 2006
  • It is well publicized that the existence of various endocrine disrupting chemicals threatens normal sexual development of many sedentary marine fishes in the coastal areas. However, a suitable marine fish species for efficient monitoring of this threatening has yet to be identified. One of the difficulties in estimating the effect of endocrine disruption in marine fish is the absence of clear distinction between testicular and ovarian structures at the early stages of sex differentiation. In search of a potential test species, we have investigated the microscopic structures of sexually undifferentiated and differentiated gonads and the susceptibility of gonadal differentiation to exogenous sex steroids during the sex differentiation period in a sedentary marine rockfish, Sebastes schlegeli. Male gonads in this species contained dark pigmentation that made them distinct from female gonads. Treatment either with $estradiol-17\;{\beta}(E_2)$ or $17\;{\alpha}-methyltestosterone$ (MT) significantly altered the sex ratios with the complete sex changes or the occurrence of ovotestis that was easily identified by the mixed structure of dimorphic gonads (coexistence of ovarian cavity/primary oocytes and dark pigmentation/seminiferous tubules). Results in this study suggest that S. schlegeli can be developed as a monitoring/test fish species for endocrine disruption in marine fish in the coastal areas.

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일본의 국립공원대회-기획.운영.시설

  • the National parks of Association of Korea
    • 공원문화
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    • s.4
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    • pp.54-57
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    • 1976
  • 국립공원대회를 개최한지 1년, 이제 제2회대회를 앞둔 우리나라의 짧은 경험에 도움이 될가하여 1975년 8월에 거행된 일본국의 제17회 자연공원대회실무책임자(송강정언-개최지암수현자연보호과장)가 기고한 "제17회 자연공원대회개초되다"를 일본국의"국립공원"지에서 초역한다.

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Food Safety of Pigment in Black Rice cv. Heugjinjubyeo (흑진주벼로부터 색소추출물의 안전성)

  • 류수노;박순직;강삼식;이은방;한상준
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.45 no.6
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    • pp.370-373
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    • 2000
  • Acute toxicity of the pigment fraction of Heugjinjubyeo was investigated in male and female mice following oral administration. Major component of pigment fraction was analyzed as cyanidin 3-glucoside (C3G), which composition content was 96%. The pigment fraction as given at the single oral doses of 1000,3000 and 9000mg/kg in male and female mice did not show any abnormal behaviours, body weight loss or other toxic symptoms during observation period of 14 days. There were no dead mice among 6 mice at a single dose of 9000mg/kg. Thus, it is concluded that the minimum lethal doses (MLD) of the pigment extract might be more than 9000 mg/kg p.o., in male and female mice.

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Studies on the Effect of Cajmium on the Physiology of Silkworm, Bombyx mori L. II. With Reference to the Change of Total Proteins and Activities of GOT and GPT in Haemolymph of Fifth Instar Silkworm Larvae (카드미움이 누에 생리에 미치는 영향 II. 누에 혈액의 Protein 합량과 GOT 및 GPT 활성의 변화에 대하여)

  • 최진섭
    • Journal of Sericultural and Entomological Science
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    • v.29 no.2
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    • pp.38-43
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    • 1987
  • The just molted larvae of the fifth instar were fed on with cadmium trated mulberry leaf and on the third day of the fifth instar the daily change of the total protein, activities of GOT and GPT in larvae haemoymph were sexually analyzed. The result obtained are summarized as follows : 1. The total haemolymph was decreased by cadmium treatment. A decreasing ratio of the total haemolymph protein was higher at the later development stage of the male fifth instar than the female fifth instar. 2. There seemed a slight difference in albumin content of the female blood along with the fifth larvae development between control and cadmium treatment where 7% decrease of blood albumin took place with cadmium treatment comparing to that of cotrol. Contrarily a decrease of blood globulin was made on both sexes. 3. The activities of GOT and GPT were inhibited by cadmium treatment.

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Zanclognatha Species in Mt. Changbai, with Description of a New Species and Two Unknown Species from China (Lepidoptera: Noctuidae) (장백산의 Zanclognatha속 1신종 기재 (나비 목 : 밤나방과) 및 중국 미기록 2종의 보고)

  • Han Hui-Lin;Park Kyu-Taek;Lu Long-Shi
    • Animal Systematics, Evolution and Diversity
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    • v.21 no.1
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    • pp.1-10
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    • 2005
  • In the lepidopteran surveys in Mt. Changbai, China, during 2000-2003, 10 species of the genus Zanclognatha Lederer of Noctuidae were recognized. Of them, a new species, Zanclognatha lui sp. novo is described, two species (Zanclognatha umbrosalis Staudinger and Z. perfractalis Bryk) are reported for the first time from China, and four species (Z. fumosa, Z. lilacina, Z. violacealis and Z. tarsipennalis) are newly known from Mt. Changbai. Synonymies, distributional ranges, photos of the genitalia, and images of the new and newly recorded species are given.

암수동체 점박이송사리(Rivulus marmoratus)에서 17 $\beta$-estradiol에 의한 갑상선 종양 유발에 대한 연구

  • 최재호;박은호
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1993.04a
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    • pp.98-98
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    • 1993
  • 어류를 이용한 독성 평가방법 및 기작에 관한 연구의 일환으로 여성 호르몬의 일종인 17$\beta$-estradiol (E$_2$)의 갑상선 종양 유발 촉진성을 검증하기 위하여 부화 후 7+1일 된 암수동체성 어류인 점박이송사리 (Rivulu marmoratu) 를 N-methyl-N'-nitrosourea (MNU) 가 10 ppm 의 농도로 녹아있는 완충 사육수에 2시간 동안 전신 노출시켜서 갑상선 종양의 유도를 촉발 (initiation) 시킨 후, E$_2$가 포함된 시험 사료 (E$_2$ 20 mg/kg diet와 E$_2$ 80 mg/kg diet) 와 이에 대한 대조 사료를 30일간 먹여 사육하였다. 그 후 80일 동안 정상사료인 염전 새우의 유생으로 키우며 매 15일 간격으로 갑상선 종양의 발생 여부를 확인하였다. 발암원 처리 후 E$_2$ 가 함유되지 않은 사료로 사육한 대조군에서는 2.4% 의 개체에서 갑상선 종양이 유도된 반면, E$_2$ 20 mg이 함유된 사료를 투여한 실험군에서의 갑상선종양 유발율은 34%로, 대조군에서 보다 14배 정도 증가하였다 (p<0.01). MNU 처리 후 E$_2$ 60 mg/kg 사료를 먹인 실험군에서의 갑상선 종양 유발율은 E$_2$ 20 mg/kg 사료를 먹인 실험군에 비하여 발암 잠재기 (latency)가 15일 정도 단축되었다. 본 실험의 결과는 E$_2$가 다단계 (multistage)로 이루어진 갑상선 종양 발생기작에 발암 촉진제로써의 역할을 한다는 것을 입증할 뿐만 아니라, 본 종이 갑상선 종양의 발생 및 촉진기작을 연구하는데 매우 적합한 실험동물 모델임을 보여준다.

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