• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 한국생물과학협회 학술발표대회
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• pp.180.1-180
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• 1995

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• Applied Microscopy
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• 제40권1호
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• pp.37-45
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• 2010

포획된 야생의 우수리땃쥐 Crocidura lasiura는 구치의 마모와 높이를 이용하여 3개의 연령군으로 분류하였고 번식과 생식기관의 계절적 변이를 조사하였다. 유수들은 구치에서 마모를 가지지 않았고 세 번째 구치 높이가 첫 번째와 두 번째 구치보다 낮았고 비번식상태만을 가졌다. 아성수들은 약간의 마모를 가졌고 세 번째 구치가 첫 번째와 두 번째 구치 높이에 도달했고 성수들은 구치에 깊은 마모를 가졌으며 아성수와 성수는 계절에 따라 번식 혹은 비번식상태를 가졌다. 조직학적 관찰을 근거로 아성수와 성수 수컷의 번식상태는 2월 초에서 10월 초까지 유지되었고 4월에 가장 높은 번식활동을 보였으며 암컷의 번식 상태는 3월 말에서 10월까지 유지되어, 수컷이 암컷보다 빨리 성적 성숙에 이르는 것으로 밝혀졌다. 반면 번식상태는 비번식기 동안 중단되며 이것은 식량자원인 토양 무척추동물의 부족때문이라 생각된다. 번식기의 아성수와 성수들은 많은 생식세포들로 채워진 확장된 세정관을 가지는 큰 정소와 많은 정자들을 가진 팽창된 부정소 미부를 가졌고 10.0 g 이상의 몸무게와 0.03 g 이상의 정소와 부정소 무게를 가졌다. 번식기의 암컷들은 4~6개의 새끼를 가진 임신상태이거나 난소에 성숙난포들과 황체를 가졌고 9.6 g 이상의 몸무게를 가졌다.

• 한국환경과학회지
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• 제28권8호
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• pp.645-654
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• 2019

This study was conducted in two breeding seasons in 2017 to identify nesting habits and breeding biology of barn swallows in Daejang-dong village, Bucheon city, suburban Seoul. Among the 77 barn swallow nests studied, there were 34 breeding nests -27 in the first and 12 in the second. The reuse rate of old nests was 51.6%. In addition to tile-roofed houses (20.6%), breeding nests were most common in brick houses (38.2%) and in slate-roofed houses (26.5%). Most breeding nests were in eaves (58.8%) and front doors (32.3%). The average clutch size was $4.8{\pm}0.9$ in the first and $4.3{\pm}0.5$ in the second. The breeding success rate was 75.0% in the first and 58.1% in the second, considering the hatching rate and the fledgling rate. It was found that the rainy season was affected by a lack of food. At least 27 pairs of nestling barn swallows and 127 young barn swallows successfully fledged were estimated to be 181. These results show that Daejang-dong village is an important suburban habitat of the Seoul metropolitan area, and that it can be used to verify the environmental conservation value of rice fields of in the Seoul metropolitan area.

• Asian-Australasian Journal of Animal Sciences
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• 제10권1호
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• pp.70-74
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• 1997

Data on 2,571 lactation records of Nili-Ravi buffaloes from four institutional herds and four field recording centers were analyzed under an animal model to see the effect of season definition on the error variance of the fitted model. Herd-year-season(HYS) was the main fixed effect along with permanent environment, breeding value and residuals as the random effects. All known relationships among the animals were considered. The error variance differed for various HYS combinations. It was minimum when then months were not grouped into seasons. The four or Five season scenarios were better than the two season scenarios. The average number of lactations represented in a HYS combination varied widely from 6 to 28. Very few subclasses for a given HYS combination warrants the use of fewer seasons for animal model evaluation of buffaloes.

• 환경생물
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• 제37권4호
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• pp.483-492
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• 2019

번식기 유부도 일대의 조수 경계부에서는 검은머리물떼새(Haematopus ostralegus osculans) 성체와 미성체가 한데 모여 복족류(서해비단고둥, Umbonium thomasi)와 이매패류를 섭식하는 것이 관찰된다. 본 연구는 성체와 미성체 간의 섭식 능력에 차이가 있는지 알아보고자 해당 먹이원을 섭식하는 개체들의 행동을 영상으로 녹화한 후 성체와 미성체로 구분하여 단위 시간당 걸음수, 먹이원 탐색시도횟수 및 탐색방법 구성비율, 섭식성공횟수, 조작시간, 머리 들어 올리기횟수를 비교하였다. 서해비단고둥을 섭식할 때 먹이원 탐색방법의 구성 비율, 이매패류를 섭식할 때 먹이원 탐색시도횟수와 머리 들어올리기횟수에서 유의한 차이를 나타냈으나, 단위 시간당 걸음수, 탐색시도횟수, 섭식성공횟수는 차이가 없었다. 결과적으로 번식기 유부도 일대에 서식하는 검은머리물떼새 미성체가 성체에 비해 비록 열세이고, 먹이원의 위치를 파악하는 능력이 부족하지만, 전반적인 섭식 능력은 성체와 유사한 수준임을 의미한다. 월동기간 동안 고도의 섭식 능력을 갖추어야 섭식이 가능한 이매패류를 지속적으로 섭식한 것에 기인한 것으로 판단된다.

• 한국임상수의학회지
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• 제21권2호
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• pp.115-121
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• 2004

The purpose of this study was to ascertain the breeding efficiency in Thoroughbred mare. A total of 106 mares were investigated for the status of follicle (462 cases), ovulation (179 cases) and pregnancy (346 cases). Of total examination, 46.8% was follicle measure to determine breeding time, and mating rate per cases examined was 39.9%. There was no correlation between reproductive results and size of follicles or endometrial edema or degrees of teasing alone. 143 cases were ovulated among 179 cases which were performed ovulation examination, and ovulation rate and fertilization rate per mating times were 79.9% and 39.0%, respectively. The use of hCG(human chorionic gonadotropin), to facilitate ovulation, presented to increase occurrence of double ovulations and twin fertilizations In conclusion, though more examination to estimate the optimal breeding time and higher mating rate was performed, fertilization rate per mating times was lower and then reproductive efficiency also became decreased. Therefore, it seemed that accurate examination of reproductive tracks, appropriate teasing programme and hCG administration before ovulation were of help to improve ovulation rate and fertilization rate.

• 아시안잔디학회지
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• 제11권1호
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• pp.73-85
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• 1997

Although zoysia grass (Zoysia spp.) has a lot of excellent chracteristics as warm-season grass, it have been limited in use due to slow establishment, low seed production, poor shade tolerance and other factors. Breeding trials have been continued from 1900's, much attentions have been paid especially in U.S.A., Korea and Japan recently. In U.S.A., more than 24 varieties had been evaluated at National Turfgrass Evaluation Program(NTEP) from 1991 to 1995 and some were regsistered as commercial. After the 6th International Turfgrass Research Conference at Japan in 1989, Japan Turfgrass In-corporation (JTI) sponsored by private companies and government carried out breeding programs for pest, salt, and shade tolerant and herbicide resistant varieties. JTI also has been trying to im-prove vigor and breed evergreen zoysia Korean breeders collected germplasms since 1960's. After USDA breeders came to Korean penesula in 1982, Korean breeders joined with USDA zoysia breeding project for several years. Many interspecific hybrids and natural selected varieties were breeded that period both in U.S.A and Korea. Breeding objectives were to extend green color period, improve leaf quality and density, and better leaf color at dormant stage. Since 1990's, zoysia grass breeding trials are getting more diverse in many points such as random amplified polymorphic DNA (RAPD) assay for ecotype identification. The objectives of this study are to evaluate germplasms in Korea, and also review the present status and future prospect in zoysia grass breeding in the world.

• Journal of Ecology and Environment
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• 제36권4호
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• pp.217-222
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• 2013

Sea temperature in the South Sea of Korea has been increased over the last decades. Seabirds are sensitive to changes in food availability in marine environment. In this study, we investigate the diet of Black-tailed gulls (Larus crassirostris) during the breeding season to identify changes of marine environment and biological response such as breeding performance in the South Sea of Korea. A total of 22 fish species or family (n = 128) from regurgitates by chicks were collected on Hongdo Island in 2002 and 2012. The most important prey item was Japanese anchovies (Engraulis japonicas). Proportion of Anchovy in diet increased in 2012 (70.5%) compared to 10 years ago (27.5%). Some species were newly found in 2012: Spotted chub mackerel (Scomber australasicus), Pacific sand lace (Ammodytes personatus), White ventral goby (Acanthogobius lactipes), Silver-strip round herring, Multicolorfin rainbowfish (Halichoeres poecilopterus), Silverside (Hypoatherina tsurugae), Surfperch (Neoditrema ransonneti) and Spotnape ponyfish (Leiognathus muchalis), but not in 2002. Especially, sub-tropic fish such as Kammal thryssa (Thryssa kammalensis), and Rosefish (Helicolenus hilgendorfi) were frequently observed in the diet of 2012. These results might reflect the increase of sea temperature in the South Sea of Korea.

• 한국육종학회지
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• 제40권4호
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• pp.439-442
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• 2008

A new spray chrysanthemum cultivar, 'Cherry Blossom' was released by National Horticultural Research Institute (NHRI), Rural Development Administration (RDA), Korea in 2007. A cross was made in 2002 between 'Relance', a spray cultivar with red petals and resistant to white rust and 'Yeonja', a spray cultivar with pink petals. Trials were conducted from 2005 to 2007 for the evaluation and selection of this cultivar, including shading culture in summer and retarding culture in autumn. The natural flowering time of "Cherry Blossom" is late October, but year-round flowering is possible by shading and lighting treatment. This cultivar is single type flowers with dark pink petals and green flower center and resistant to white rust. It is very stable color of petals when the variety is cultivated under high temperature conditions in summer season. The diameter of flower is 55.0 mm. The number of flowers per stem is 10.5 and the number of petals per flower is 24.0. The days to flowering under the short day treatment is about 45 in spring season.

• International Journal of Industrial Entomology and Biomaterials
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• 제2권1호
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• pp.65-68
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• 2001

A new silkworm variety, Chunsujam, for spring rearing season is F$_1$ hybrid between Japanese race Jam145 bred by 8459/8711 and Chinese race Jam146 by 8544/M8626. Jam145, Japanese parent of the Chunsujam, showed high GCA in pupation rate and Jam146, Chinese parent, showed high GCA in pupation rate and single cocoon weight. In the local adaptability test performed at 8 local areas in spring of 1999, Chunsujam was 5% higher in larval weight, 3% in single cocoon weight, and 4% in cocoon yield from 10,000 of the 3rd molted larvae, respectively, than the check variety Baegokjam.