• 환경생물
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• 제24권1호
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• pp.1-6
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• 2006

Abstract - Global decline in wildlife mammals has been accelerated during past decades. Especially the conservation the wild life mammals in polar areas, is urgent. In an effort to understand the reproduction of the seals dwelling in the polar area, spermatogenesis in the seals was reviewed. Seals breed seasonally and in most of the seal species, delayed implantation is frequently observed. To date, histological and endocrinological evaluation revealed highly cyclic nature in supermatogenesis and steroidogenesis in testis. Seasonal changes in blood testosterone level together with melatonin is closely related with changes in light cycle between summer and winter. In adult testis at breeding seasons, spermatogenesis is manifested by consecutive 18 stages of germ cell development. Three kinds of Leydig cells different in steroidogenic activity as well as cellular morphology appear during the testis development. During non-breeding season, spermatogenic arrest and Leydig cell hypoplasia are frequently found. Interestingly, blood circulation through the anastomoses of pelvic veins cooled the testes and thus guarantees spermatogenesis within the body trunk. Endocrine disruptors and heavy metals have been found in the body tissues of several seals species and alter steroidogenesis in seals, suggesting environmental pollutants together with decrease in habitats are potentially threatening the reproductive success in seal species.

• Journal of Plant Biotechnology
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• 제37권4호
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• pp.400-407
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• 2010

Zoysiagrass (Zoysia japonica Steud.), also called Korean or Japanese lawngrass, is the most popular warm-season turfgrass in Korea and is widely used for home lawns, parks, roadsides, golf courses and athletic fields. Its use is rapidly expanding in Korea and the other countries, due to its excellent characteristics which include tolerance to heat, drought and salinity. As the utilization area of this turfgrass increases, there is an increase in the demand for improved cultivars with disease and insect tolerance or with herbicide-tolerance or with extended greening periods. Conventional breeding methods have been used to improve the traits described above with limited success. However, with the advances in biotechnology, genetic transformation can be utilized for turfgrass improvement. In this paper, we review recent progress in biotechnological improvement of zoysiagrass and discuss future molecular breeding of this species.

• 한국육종학회지
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• 제40권4호
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• pp.361-370
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• 2008

In order to better understand the morphological differentiation of the two cultivated types of Perilla crop and their weedy types in Korea and Japan, we studied the variation of 62 accessions by examining 15 morphological characteristics. By using ANOVA (one-way analysis of variance), we determined that var. frutescens and var. crispa showed significant morphological differences in terms of plant height and seed weight. Furthermore, cultivated var. frutescens and var. crispa could also be clearly discriminated from one another using PCA (principal component analysis). Specifically, quantitative and qualitative characteristics such as plant height, seed weight, degree of pubescence, shape of leaf, color of leaf, fragrance of plant, color of flower, color of stem and seed size greatly contributed to differences seen in the positive and negative direction on the first axis. In our study, most accessions of cultivated var. frutescens and those of its weedy type could be clearly discriminated from one another, however, most accessions of cultivated and weedy types of var. crispa were not clearly discriminated by the ANOVA and PCA analyses. These results indicated that cultivated var. frutescens can be considered to be a domesticated form, while the cultivated var. crispa can not be considered to be a domesticated form in Korea and Japan. It is our belief that our results concerning the morphological variations among cultivated types of Perilla crop and their weedy types in Korea and Japan will help ensure the long-term success of breeding programs and maximize the use of the germplasm resources in Korea.

• Asian-Australasian Journal of Animal Sciences
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• 제22권10호
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• pp.1351-1358
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• 2009

Parentage tests using polymorphic DNA marker are commonly performed to avoid incorrect recording of the parental information of livestock animals, and single-nucleotide polymorphisms (SNPs) are becoming the method of choice. In Japanese Black cattle, parentage tests based on the exclusion method using microsatellite markers are currently conducted; however, an alternative SNP system aimed at parentage tests has recently been developed. In the present study, two types of simulations were conducted using the pedigree data of two subpopulations in the breed (subpopulations of Hyogo and Shimane prefectures) in order to examine the effect of actual genetic and breeding structures. The first simulation (simulation 1) investigated the usefulness of SNPs for excluding a close relative of the true sire; the second one (simulation 2) investigated the accuracy of sire identification tests for multiple full-sib putative sires by a combined method of exclusion and paternity assignment based on the LOD score. The success rates of excluding a single fullsib and sire of the true sires were, respectively, 0.9915 and 0.9852 in Hyogo and 0.9848 and 0.9852 in Shimane, when 50 SNPs with minor allele frequency (MAF: q) of 0.25${\leq}$q${\leq}$0.35 were used in simulation 1. The success rates of sire identification tests based solely on the exclusion method were relatively low in simulation 2. However, assuming that 50 SNPs with MAF of 0.25${\leq}$q${\leq}$0.35 or 0.45${\leq}$q${\leq}$0.5 were available, the total success rates including achievements due to paternity assignment were, respectively, 0.9430 and 0.9681 in Hyogo and 0.8999 and 0.9399 for Shimane, even when each true sire was assumed to compete with 50 full-sibs.

• Journal of Animal Science and Technology
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• 제61권3호
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• pp.163-169
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• 2019

Detection of estrus is an essential factor as a method of successful breeding in the sow. As increasing the adaption of the information and communication technology (ICT) into swine industry, this study focuses on a possibility and quantification of standing time, vulva and body temperature as methods of estrus detection, comparing each time and temperature in estrus and non-estrus period, and analyzing each success rate of new and existing methods. Ultrasonic sensor array and digital infrared thermography were used to evaluate whether new methods such as standing time and number, and vulva and skin temperature can be replaced, or these methods can be quantifiable in estrus period. Ultrasonic sensor array was installed beside the stall and digital infrared thermography was placed in the rear of sow to collect the dates of sow in estrus and non-estrus period. This study showed total standing time, number and number over 10 minutes, and vulva temperature of the sow in estrus period were increased (p < 0.05) compared with those of sow in non-estrus period, respectively. Detection of estrus using standing time and vulva temperature tended (p = 0.06) to increase the success rate when artificial insemination (AI) was performed. In conclusion, standing time and vulva temperature increased when estrus happened. Success rate of AI of sow using these methods showed an increasing trend. Therefore, existing method using the naked eye can be replaced to new method such as vulvar temperature and standing time when detecting the estrus.

• 한국가축번식학회지
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• 제16권1호
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• pp.39-46
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• 1992

In viro fertilizatin is very important in both human clinical practice and animal breeding. However, the success rate of in vitro fertilization is not high. The purpose of this study ws to determine wheter in the vitro fertilization and culture of porcine oocyte using a hydrogel chamber were possible or not. Hydrogel chambers were made of polymerized 2-hydroxyethyl methacrylate. Matured follicular oocytes in Waymouth's medium and T L Hepes medium, tubal oocytes, and preincubated sperm in M199 medium were treansferred into the lumen of the hydrogel chambers. The chambers containing porcine oocytes and spermatozoa implanted into the mouse peritioneal cavity, and ova were examined after the recovery of the chambers at 84 hours after preservation start. The result was shown that fertilization and culture of porcine oocytes were successfully achieved inside of the hydrogel chamber.

• Animal cells and systems
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• 제13권1호
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• pp.91-96
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• 2009

The size of song repertoires mainly provides evidence for explaining sexual selection for female choice as well as male-male competition. We investigated the role of oriental great reed warbler songs (Acrocephalus orientalis) of breeding territorial males. Early arrived males possessed larger song repertoires, paired earlier, and tended to become polygynous. No correlation was found between arrival date and territory size, but polygynous males significantly occupied larger territories than non polygynous males. Song sharing was low among males and the degree of similarity did not relate with spatial distance. Our results suggest that song repertoire of the oriental great reed warbler males play a role in female choice, where territory quality may affect male pairing success.

• Asian-Australasian Journal of Animal Sciences
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• 제5권1호
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• pp.29-32
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• 1992

The effects of prostaglandins (PG) and indomethacin, a PG synthesis inhibitor, on ovulation in the perfused fowl ovary were studied. Laying hens were killed by cutting the jugular vein 18-19 h before expected ovulation of the second follicle of a clutch sequence. The cannulated ovary was dissected free and connected with a recycling perfusion apparatus. Agents to be studied for their effects on ovulation were added to the perfusion fluid. $PGF_{2{\alpha}}$ at 0.1 and 1 mg/l induced ovulation, with a success rate of 25% and 30%, respectively. The same doses of $PGE_2$ were effective at 60% and 63%, respectively. Indomethacin partially blocked gonadotrophin-induced ovulation. It is suggested that PGs may play a supportive role in the process of follicular rupture in the domestic fowl.

• 농촌지도와개발
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• 제3권1호
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• pp.95-106
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• 1996

Pig industry has been one of the most important sector in Taiwan since 1970s, and produce one fourth of the agricultural income. The industry has made great improvements in breeding, raising and quality production while marketing and processing have interrelated efficiently with production. As one of the mayor factor to the present success, cooperative research and extension has been institutionalized among the government agencies, farmer`s associations and research institutions, inter-linked with the farmer`s problem-solving process. At present, the industry is seeking an appropriate strategy and measures to upgrade the pollution control and cost efficiency in production. This paper reviewed an industry case historically in Taiwan in order to draw the implications to the emerging farm sector in which international competitiveness and quality improvement are to be considered.

• 한국습지학회지
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• 제18권4호
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• pp.350-356
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• 2016

동물의 번식 성공에 가장 큰 요인은 먹이의 선택이고 먹이의 선택은 서식지의 질과 양에 의해 결정되어 지며, 생물량이 높은 습지의 경우 생태계 기능의 지표로서 황조롱이의 사냥 장소의 선택은 서식 장소의 질과 양을 알아보는 중요한 단서가 될 것으로 예상된다. 본 연구는 충남 공주시 유구읍의 황조롱이 사냥장소에 대해 4가지 유형(초지, 논, 밭, 하천변)으로 구분하여, 번식시기인 3월에서 6월까지 3년간 (2014년~2016년) 황조롱이의 행동을 기록하였다. 조사결과, 사냥의 장소는 하천변에서 높은 사냥행동을 보였고, 비행사냥은 5월과 6월에 많이 하는 것으로 조사되었다. 또한 비행사냥의 주요 획득 먹이는 포유류(쥐), 착지행동의 주요 획득 먹이는 곤충류로 조사되었다. 이에 따라, 하천변에서는 주로 비행사냥이 이루어졌으며, 초지나 논과 밭에서는 착지 행동이 비행행동에 비해 높게 조사되었다. 사냥이 이루어지는 지점의 식물이 땅을 덮는 피도는 사냥지역별 차이를 보였으나 식물의 높이는 차이를 보이지 않는 것으로 확인되었고, 사냥 방법에 따른 식물의 높이는 포유류(쥐)를 잡기 위한 비행사냥이 착지사냥보다 낮은 높이를 선호하는 것으로 분석되었다. 이러한 결과들을 바탕으로 황조롱이의 번식기 먹이 선택에서 하천변은 매우 중요한 환경 요소로 판단된다.