• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.3
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• pp.290-297
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• 2011

The phenology of Campylaephora hypnaeoides J. Agardh and optimal conditions for carpospore release, growth and reproduction were examined in the field and in the laboratory from January to December 2007. In the field population of C. hypnaeoides, approximately 50% of the plants were vegetative during the study period. Additionally, the percentages of carposporophytes and tetrasporophytes were maximal in April (37%) and June (57%), respectively. Maximum growth in plant length, dry weight, and hook number coincided with the tetrasporophyte reproductive peak in the field. In culture, carpospore release, sporeling growth and reproduction were affected by environmental factors such as daylength, temperature, and salinity. The liberation of carpospores was maximum under continuous light and at a combination of $15^{\circ}C$ and $10\;{\mu}mol$ photons $m^{-2}\;s^{-1}$. Maximum growth of tetrasporophyte sporelings occurred at a combination of $20\;{\mu}mol$ photons $m^{-2}\;s^{-1}$ of constant light and $25^{\circ}C$. However, the growth of gametophyte sporelings was maximal under $40\;{\mu}mol$ photons $m^{-2}\;s^{-1}$ of constant light and in a combination of $20^{\circ}C$ and 35 psu. The tetrasporophyte sporelings were grew faster than gametophytes, indicating that gametophyte- and tetrasporophyte-sporelings have different physiological responses to irradiance and temperature. Tetrasporangial branches and cystocarps of C. hypnaeoides were produced from carpospores and tetraspores within 1 month, and they were stimulated at high temperature and irradiance levels. In conclusion, C. hypnaeoides should be seeded using carpospores during early winter (November-December) because cystocarps are easily identified by fishermen, and tetrasporophytes grow faster than gametophytes.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.1
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• pp.1-5
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• 2015

This study assessed the impacts of grazing and barn feeding on the reproductive performance of black goats and the growth performance of goatlings to gather basic data for the establishment of an ideal goat-breeding system. A total of 36 Korean black goats were grouped by feeding system (a pasture grazing group and a barn feeding group, n=18) over the 8-month study period from April to November 2011. The difference between the singleton pregnancy rate of the grazing group, measured at 31.5%, and the barn-feeding group's 37.0% was not statistically significant. Also, breeding type did not yield any meaningful differences, with 1.76 live births recorded for the grazing group and 1.69 recorded for the barn-feeding group. In regard to weaner goats, the grazing group showed a higher number compared to the barn-feeding group (p=0.11). The birth weight of the grazing group was measured at 2.3 kg, while that of the barn-feeding group was 2.29 kg, with breeding type yielding no significant differences. The grazing group's weight at 90 days of age was 9.97 kg, which was higher than the barn-feeding group's 9.45 kg (p=0.09). The grazing group showed higher daily weight gain during the lactation period than the barn-feeding group (p=0.13). Overall, with breeding type considered, the grazing group did not show significant differences in terms of the number of live births and birth weights compared to the barn-feeding group; however, the grazing group showed better outcomes in terms of daily weight gain. As it has been shown that grazing satisfies the physiological needs of goats more effectively than barn feeding, we believe that it contributes to the farming of healthy goats.

• Journal of Animal Environmental Science
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• v.15 no.1
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• pp.1-8
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• 2009

This study was conducted to analyze the effects of sow breeding environment on the reproduction in the first litter in a large-sized hog farm, located in Dangjin-gun, Chungnam from July 1st, 2007 to June 30th, 2008 and provide basic information to improve the sow productivity in a family farming sows. The results obtained were as follows; 1. The gestation periods were proved to be similar without significant differences between indoor and outdoor breeding grounds, The average of farrowing rate was 91.91%, and 92.54% farrowing rate of out-door ground breeding sows was slightly greater than 91.57% of group-housed sows, but there was no significance between two groups. 2. The average of total litter size and the number of born alive per litter were 9.81 and 9.02, respectively. The number of total number was 0.98 and the number of born alive per litter was 1.18 in the outdoor-ground breeding sows, which was significantly greater than group-housed sows(p<0.001). 3. The number(rate) of piglets stillborn was 0.22(2.10%) from the outdoor-ground breeding sows was significantly greater, compared with 0.33(3.53%) from group-housed sows(p<0.01). The number of piglets culled was 0.23(2.27%) and 0.26(2.77%), in the out-door ground breeding sows and in group-housed sows, respectively and it was not significantly similar between two groups. And, the number of mummies was 0.21(2.1%) and 0.28(2.29%), in the out-door ground breeding sows and in group-housed sows, respectively, which showed no significance. 4. The weaning number in the playground breeding sows was 9.48 and it was significantly greater than that in the group-housed sows(p<0.001). The average of weaned age was observed to be 22.91 days. The weaned age in the out-door ground breeding sows was 22.39 days, and it was significantly smaller than that in group-housed sows(p<0.001). The breeding rate for the weaning of pigs was satisfactory as 96.82%, but there was no significant difference between two groups.

• Korean Journal of Environment and Ecology
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• v.30 no.6
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• pp.977-985
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• 2016

The captive breeding program of the Reeve's turtle (Mauremys reevesii), which is designated as an endangered category II species by the Korean Ministry of Environment, has developed, but the reproductive physiology of the species is still not fully understood. In this study, we investigated seasonal changes in the sex steroid levels, the number and size of follicles and eggs and male-female interactive behaviors of hibernated and non-hibernated turtles between November 2014 and October 2015. Plasma estradiol level in females increased from July and peaked in the period from August to October. Plasma testosterone level in males peaked between August and September and was the lowest in March, although there were some variations depending on the patterns of hibernation. Hibernated females had fully developed eggs between early May and middle July and laid eggs between early June and late July, but non-hibernated females had eggs between early April and early June and also between middle August and late November, and laid eggs in early June, mid-October, and early February. These results suggest that hibernation could be essential for normal follicular and egg developments. Male-female interactive behaviors including courtship intensified from late August and peaked in October and November. Our findings suggest that mating period of this species is directly related to increased steroid hormone levels, but follicular and egg developments in females are not. Our results could be very useful to the successful operation of captive rearing programs of the endangered Reeve' sturtles.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.7-8
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• 2003

Since it was first reported in 1997, somatic cell cloning has been demonstrated in several other mammalian species. On the mouse, it can be cloned from embryonic stem (ES) cells, fetus-derived cells, and adult-derived cells, both male and female. While cloning efficiencies range from 0 to 20%, rates of just 1-2% are typical (i.e. one or two live offspring per one hundred initial embryos). Recently, abnormalities in mice cloned from somatic cells have been reported, such as abnormal gene expression in embryo (Boiani et al., 2001, Bortvin et al., 2003), abnormal placenta (Wakayama and Yanagimachi 1999), obesity (Tamashiro et ai, 2000, 2002) or early death (Ogonuki et al., 2002). Such abnormalities notwithstanding, success in generating cloned offspring has opened new avenues of investigation and provides a valuable tool that basic research scientists have employed to study complex processes such as genomic reprogramming, imprinting and embryonic development. On the other hand, mouse ES cell lines can also be generated from adult somatic cells via nuclear transfer. These 'ntES cells' are capable of differentiation into an extensive variety of cell types in vitro, as well assperm and oocytes in vivo. Interestingly, the establish rate of ntES cell line from cloned blastocyst is much higher than the success rate of cloned mouse. It is also possible to make cloned mice from ntES cell nuclei as donor, but this serial nuclear transfer method could not improved the cloning efficiency. Might be ntES cell has both character between ES cell and somatic cell. A number of potential agricultural and clinical applications are also are being explored, including the reproductive cloning of farm animals and therapeutic cloning for human cell, tissue, and organ replacement. This talk seeks to describe both the relationship between nucleus donor cell type and cloning success rate, and methods for establishing ntES cell lines. (중략)

• Korean Journal of Ecology and Environment
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• v.42 no.4
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• pp.422-431
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• 2009

This study was to provide basic data for aquatic ecosystem research using fishes. Field sampling was carried out at five selected sites of Gap Stream, and fish samples, especially for a selection of sentinel species were collected three times in June, September, and October 2007. We analyzed total length distribution of Zacco platypus in relation with the season and the sampling sites, and then compared with total body weight, condition factor (K), and age distribution of the fish. The fish population data were compared with physico-chemical water quality, obtained from the Ministry of Environment, Korea. Water quality analysis showed a significant nutrient enrichment, based on total nitrogen (TN) and total phosphorus (TP), and organic matter pollution, based on biological oxygen demand (BOD) and chemical oxygen demand (COD) in the Site 5, which is directly influenced by wastewater disposal plant (WDP). Population analysis of the sentinel species showed that the total number of individuals, age distribution, and the population size-structure were influenced by the effluents from the WDP, and that reproductive failure of young-age population were evident in Site 5. According to the relation analysis of total weight to K, the disturbed population was mainly attributed to combined effects of habitat modifications and chemical degradations. Regression analysis of K values against water quality parameters showed significant (p<0.05) positive relations with nutrient and organic matter contents. Our data suggest that the population structure using a sentinel fish species reflected the ambient water quality in the stream and that diagnosis of aquatic ecosystem health using Z. platypus population may be practical for water resource and ecosystem conservations.

• Korean Journal of Veterinary Research
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• v.37 no.1
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• pp.25-39
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• 1997

The morphology of the ductuli efferentes of the Korean native pheasants were observed in order to obtain a basic data for further studying reproductive physiology and other male genital organs. The mature (14-16 months after hatching) male pheasants were used in this study. The specimens from pheasants were collected on a monthly basis. The general morphological changes of the ductuli efferentes were observed with hematoxylineosin stain, and semithin section by light microscope. The ultrastructural changes of the ductuli efferentes were investigated with ultrathin section by transmission electron microscope. The results obtained are summarized as follows : 1. During the breeding season, the average height of ductuli efferentes epithelium was $23.45{\pm}2.34{\mu}m$ and was largely decreased by $17.85{\pm}2.01{\mu}m$ during the non-breeding season. The thickeness of interstitial tissue was comparatively increased during the non-breeding season. 2. During the breeding season, the epithelial cells of ductuli efferentes were well developed. During the non-breeding season, epithelial layer and lumen of ductuli efferentes, were markedley reduced compared with those of breeding season. 3. Morphological changes of the ductuli efferentes underwent periodic changes paralleling to the spermatogenic cycle. 4. At least two different cell types were identified in the epithelium of ductuli efferentes, namely non-ciliated and ciliated cells. 5. The ciliated cells possess many vesicles, slightly smaller than those of the non-ciliated cells. 6. The ciliated cells contained numerous mitochondria, smooth and rough endoplasmic reticulum, Golgi complex, lysosome, and oval nuclei. The non-ciliated cells had a irregular nuclei and a cytoplasm containing few organelles. 7. During the breeding season, a number of vesicles, rough and smooth endoplasmic reticulum, Golgi complex, and mitochondria were distinctively showed in the epithelial cells but in the non-breeding season only a few observed.

• The Korea Journal of Herbology
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• v.34 no.6
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• pp.63-70
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• 2019

Objective : Arnebiae Radix, the roots of Arnebia euchroma (Royle) Johnst. or A. guttata Bunge, is a well-known traditional herbal medicine in East Asia. In the Korean Pharmacopoeia, three authentic species, including two Arnebia and Lithospermum erythrorhizon Sieb. et Zucc. have recognized as a Lithospermi Radix. But, the morphological and taxonomic information of two authentic Arnebia species lacks date since their distribution and difficulty of accessing the natural habitats. Methods : A full description of the external morphological characteristics of vegetative and reproductive organs in the original plants was carried out using digital calipers and stereoscope. For providing their taxonomic and nomenclatural synonyms, we reviewed various plant checklists and taxonomic literature. Results : This study provides taxonomic information of A. euchroma and A. guttata based on a morphological examination of authentic plant individuals and field observations. Detailed descriptions of the two Arnebia species, major quantitative and qualitative characteristics, nomenclatural reviews, distribution maps, and lists of voucher specimens examined are provided. The shape of leaves, root length, stem number, calyx length and pubescence as well as corolla color were useful characteristics for identification. Moreover, we confirmed that A. euchroma and A. guttata are clearly heterostylous species. Conclusion : Our research provides valuable basic information that could be used as quality control for distinguishing between Arnebiae Radix and its adulterants. These results will help in the understanding of authentic plants and also provide the verified materials and voucher information.

• Journal of Embryo Transfer
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• v.22 no.3
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• pp.191-194
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• 2007

The purpose of the present study was to set up basic information of size and status of ovaries by using ultrasonography to retrieve in vivo matured oocytes with ovum pick- up method. Ovaries were collected from the abattoir in Jeju in May and June which is breeding season. When the size of ovaries on ultrasonography was compared with real size measured by caliper, no significant difference was shown (p<0.05). The number of preovulatory follicles (>21mm) was investigated with ultrasonography and naked eyes. Ultrasonography group had 0.83 preovulatory follicles per ovary and naked-eye group had 0.75 preovulatory follicle per ovary and their average size was 2.86 cm and 2.34 cm, respectively. The average number of follicle was 4.25 with ultrasonography and 4.38 with naked eyes. There was no significant difference considering the size of follicle and number of follicle between ultrasonography and actual size except for the size of preovulatory follicle, suggesting that information of ultrasonography is able to use for OPU or other reproductive technology of mare.

• Korean Journal of Animal Reproduction
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• v.9 no.2
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• pp.124-132
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• 1985

The work was conducted to clarify the development of testes and histological changes of the Seminiferous tubules that is the Surface area, diameter, length of the tubules and the process of Spermatic cells growth in Seminal epithelium in relation to Sexual maturity of the meat-type cockerels. In addition the present experiments were planned to gain some basic data helpful for the study of reproductive physiology in meat-type cockerels and also to compare the histological changes Seminiferous tubules between egg and general purpose type cockerels. 1. The growth pattern of body weight, testes and comb was classified into four phase according to age. Body weight increased up to about 2kg at 2nd stage and to 4.3kg at 4th stage while at 3rd stage the growth rate of body weight was slower. The tests developed slowly until 22 weeks of age with no correlation to the growth of body weight. However, it grew rapidly afterwards, reaching 27.79$\pm$9.26gm and 42.46$\pm$5.33 gm at 24 and 28 weeks of age, respectively. The spermatozoa was seen first at 24 weeks of age. On the other hand, comb grew at similar rate to the testes, weighing on the average 21.78$\pm$6.48gm and 41.42$\pm$1.25gm at 24 and 28 weeks of age, respectively. 2. The areal rate of the Seminiferous tubules to interstitial tissues was 66%:34% at 2 weeks of age and the rate of the former increased in comparison to that of the latter as they grew older, becoming 94%:7% between at 24 weeks of age, when the testes weight increased rapidly too. 3. Diameter of Seminiferous tubules at 2 weeks of age was 42.76$\pm$1.04$\mu$m and then it gradually increased as the testes grew until 22 weeks of age, when it grew rapidly, increasing about 2.9 times of those of 2 weeks and at last increased up to 5 times at 24 weeks. 4. Length of Seminiferous tubules was 4.5cm at 2 weeks and then it was gradually increased. At 22 weeks old the length of tubules was icnreased rapidly being 321 meter and increased more than double, being 658 meter at 24 weeks old. 5. The cells of Seminal epithelium developed poorly and the number of cells were relatively few until 16 weeks old. Afterwards the cells increased rapidly in number and at 18 weeks, the number became twice of those of 16 weeks, reaching 140.43$\pm$43.6. At 24 weeks the cells increased more rapidly, reaching to 10 layers and Spermatozoa were first time seen.