• The Korean Journal of Ecology
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• 제21권3호
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• pp.187-193
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• 1998

Seasonal changes of nitrogen fixation and growth characteristics of Melilotus suaveolens population under different light conditions were quantitatively analyzed during growting period. Height growth of M. suaveolens population was promoted after April and the shade (site 2) showed 10-20% increase of height growth in compared with that of sunny (site 1). Seasonal changes of biomass were in creased after March, the biomass at site 1 attained 78.5% that of site 2 in May. Chlorophyll content was maintained high value from March to April but, Chlorophyll content of leaf at site 1 was decreased 11.7% compared to that of site 2 in May. The nitrogen content of each organ of M. suaveolens showed higher value in March and then decreased, the high nitrogen contents of reproductive organ were achieved at the flowering stage at site 1. The root nodule of M. suaveolens population appeared in March and showed maximum value in early June and decreased remarkably after July, the amount of nodule formation of M. suaveolens at site 2 showed higher than that of site 1. The nitrogen fixation activity of root nodule of M. suaveolens initiated with shoot growth and showed maximum value in mid April, and attained second peak in early June and then decreased after July. The total nitrogen fixation of the plant showed higher value at site 2 than that of site 1. From the overall results, M. suaveolens showed increased growth under half-shady, well ventilated barren soil than fertile sunny site.

• Journal of Ecology and Environment
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• 제30권2호
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• pp.127-133
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• 2007

The effects of water flow rate and phytoplankton concentration on the growth of the sandy shore clam Gafrarium tumidum was investigated in a laboratory flume study using a $3{\times}3$ factorial design. After 60 days, shell length, shell weight and tissue dry weight increased significantly with phytoplankton concentration. For the effect of flow rate, growth was faster when flow rate increased from low to medium level; further increases in flow rate, however, either did not sustain faster growth or resulted in a reduction in growth. The condition index (CI) of a standard-sized clam was significantly higher at low flow rate than at medium and high flow rates and was negatively correlated with phytoplankton concentration. The uncoupled growth of shell and tissue in response to flow rate and phytoplankton concentration may be adaptations to low food environments, so that energy can either be stored to sustain life or reserved for gametogenesis during the reproductive period.

• 한국수정란이식학회지
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• 제28권4호
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• pp.325-335
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• 2013

The study was set for one year to measure the effects of concentrate supplementation on reproductive performances and semen quality in indigenous rams. The study was conducted at the Department of Surgery and Obstetrics, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh, Bangladesh during the period from May 2011 to April 2012. Forteen ram lambs (4~5 months) were randomly divided into two equal groups (n=7); supplemented vs control. The animals of control group were maintained on natural grazing. Along with natural grazing the supplemented group was on supplemented feeding. The concentrate supplementation (Wheat bran, Crushed maize, Soy bean meal, Fish meal, DCP powder, Vitamin mineral premix, Salt) was provided @ 300 g/head /day to the supplemented group. Body weight, scrotal circumference, BCS and libido index were measured weekly. Age, body weight and scrotal circumference at puberty were recorded. Semen was collected once in a weak using artificial vagina and chilled at $5^{\circ}C$ for 48h for evaluation. Concentrate supplementation did not influence (p>0.05) body condition score, age, weight, scrotal circumference at puberty and libido index. Final body weight (kg), growth rate (g/d), scrotal circumference (cm) and scrotal growth rate (mm/15d) were significantly (p<0.05) higher in supplemented group of rams compared to control. Volume, concentration, motility and membrane potentiality of spermatozoa were varied significantly (p<0.05) in supplemented and control groups. However, density, mass motility, viability and sperm with normal acrosome, midpiece and tail were not differed insignificantly (p>0.05) in different observation times. It was concluded that concentrate supplementation with free grazing improved weight and scrotal circumference gain and semen production with increased quality in indigenous ram.

• 한국발생생물학회지:발생과생식
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• 제17권3호
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• pp.269-274
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• 2013

This study was performed to evaluate the effects of fibroblast co-culture on in vitro maturation (IVM) of prepubertal mouse preantral follicles. The intact preantral follicles were obtained from the ovaries of 12-14 day old mice and these were cultured individually in ${\alpha}$-minimal essential medium (${\alpha}$-MEM) supplemented with 5% fetal bovine serum (FBS), $100mIU/m{\ell}$ recombinant follicle stimulating hormone (rFSH), 1% insulin-transferrin-selenium, $100{\mu}g/ml$ penicillin and $50{\mu}g/m{\ell}$ streptomycin as base medium for 12 days. A total of 200 follicles were cultured in base medium co-cultured with mouse embryonic fibroblast (MEF) (MEF group) (n=100) or only base medium as control group (n=100). Survival rate of follicles on day 12 of culture were significantly higher in the MEF group of 90.0%, compared with 77.0% of the control group (p=0.021). Follicle diameters on day 6 and 8 of the culture period were significantly larger in the MEF group than those in the control group (p=0.021, p=0.007, respectively). Estradiol levels in culture media on day 4, 6, 8, 10 and 12 of the culture period were significantly higher in the MEF group (p=0.043, p=0.021, p=0.006, p<0.001 and p=0.008, retrospectively). Our data suggest that MEF cell co-culture on IVM of mouse preantral follicle increases survival rate and promotes follicular growth and steroid production.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• 제15권10호
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• pp.1453-1457
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• 2002

The experiment was conducted to find out the effect of 4 feeding systems on growth, feed intake, eating behavior, lactation performance, gestation period, post-partum heat period, conception rate and parasitic infestation of Black Bengal goat. Twenty four does of approximately 1 year of age were randomly selected for 4 treatment (feeding systems) groups having 6 replications in each. Treatments were stall feeding ($T_1$), tethering ($T_2$), restricted grazing ($T_3$) and grazing ($T_4$). $T_1$ group was housed continuously and adequate amounts of natural grass were supplied for ad libitum feeding. $T_2$ group was tethered for grazing natural grass from 8 a.m. to 4 p.m. being moved at one hour intervals. Goats of $T_3$ group were allowed grazing from 8 a.m. to 1 p.m. $T_4$ group was grazed from 8 a. m. to 4 p.m. Concentrate supplement was given at the rate of 150 g per day per goat for all of the treatment groups. Duration of experiment was 219 days. Daily live weight gain was significantly (p<0.05) higher in case of stall fed goats than that of others. DM intake also significantly (p<0.05) differed among the treatment groups and was 3.40 3.95, 3.76 and 4.05 per cent of their live weight for stall feeding, tethering, restricted grazing and grazing groups, respectively. Rate of rumination was significantly (p<0.05) higher in case of tethering group of goats than that of others. Birth weight of kids, milk yield, lactation period and post-partum heat period were significantly higher in case of stall fed goats than others. Tethering group showed significantly (p<0.05) higher litter size than others. Infestation rate of Fasciola was significantly (p<0.05) higher in the grazing group. In conclusion, it may be stated that among these feeding groups overall performance of stall fed goats was more satisfactory, and that the tethering group showed better performance than the others.

• 한국균학회지
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• 제4권1호
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• pp.31-44
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• 1976

팽이버섯[Flammulina velutipes(Curt. ex Fr.) Sing.] 톱밥 재배(栽培)에 있어서 배지(培地)의 각종(各種) 영양급원(營養給源)의 첨가효과(添加效果) 및 배지(培地)의 물리적(物理的) 향상(向上)을 위(爲)한 방법(方法)을 구명(究明)하는 한편 재배과정중(栽培過程中) 일어나는 배지(培地)의 화학적(化學的) 성분(成分) 변화(變化)를 조사(調査)하여 팽이버섯의 영양요구(營養要求)에 대(對)한 기초자료(基礎資料)를 얻고자 일련(一連)의 시험(試驗)을 수행(遂行)한 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 포플러 톱밥에 미강(米糠), 밀기울 및 우분(牛糞)을 첨가비(添加比)를 달리하여 혼합(混合)한 배지(培地)에서 팽이버섯을 병재배(栽培)한 결과(結果), 포플러 톱밥 10에 미강(米糠) 3을 혼합한 처리구(處理區)에서 자실체(子實體) 수량(收量)이 84.4g/병(배지(培地)280g)으로서 가장 높았고 비교적(比較的) 수량(收量)이 높았던 포플러 톱밥 10에 미강(米糠) 3, 2 및 밀기울 3을 혼합한 처리구(處理區)에서 배지(培地)의 전질소(全窒素), 당류(糖類)와 가량(加量)의 함량이 높았다. 2. 톱밥 배지(培地)의 추출액(抽出液) 배지(培地)에서의 균사생장(菌絲生長)은 탄소(炭素) 및 질소(窒素) 등(等) 영양요소(營養要素)가 부족(不足)한 톱밥 단용구(單用區)나 우분첨가구(牛糞添加區)에서 극(極)히 저조(低調)하였으며, 톱밥 배지상(培地上)에서는 이들 처리구(處理區)에서 균사생장(菌絲生長) 속도(速度)는 빨랐으나 균사밀도(菌絲密度)는 현저(顯著)히 떨어졌다. 3. 가비중(假比重) 및 수분함량(水分含量)을 달리한 포플러 톱밥10+미강(米糠) 3 혼합배지(混合培地)에서 균사생장(菌絲生長)은 수분함량(水分含量) 72%, 가비중(假比重) 0.2에서 촉진(促進)되었으나 자실체(子實體) 수량(收量)은 가비중(假比重) 0.3, 수분함량(水分含量) 67%에서 가장 높았다. 4. 포플러 톱밥에 첨가(添加)되는 미강량(米糠量)이 증가(增加)됨에 따라 배지(培地)의 무게 감소율(減少率)은 커지며, 회분함량(灰分含量)도 증가(增加)하는 경향(傾向)을 보였고 종균(種菌) 접종(接種) 75일(日) 후(後) 무게 감소율(減少率)은 $17.8{\sim}28.8%$ 범위(範圍)였으며 회분(灰分)은 $10.1{\sim}13.2%$가 증가(增加)되었다. 5. 전재배기간중(全栽培期間中) cellulose는 $11{\sim}14%$, lignin은 $3{\sim}4%$의 절대량(絶對量)의 감소(減少)를 보여 포플러 톱밥에 첨가(添加)되는 미강량(米糠量)에 따른 큰 차이(差異)가 없었으며 가용성(可溶性) 당(糖)의 함량(含量)은 증가(增加)하는 경향(傾向)을 보였다. 6. 재배기간중(栽培期間中) 전질소(全窒素)는 시료(試料)에 대(對)한 함량(含量)은 증가(增加)하며 절대량(絶對量)은 감소(減少)하였으나 극(極)히 미소(微小)한 함량변화(含量變化)를 보였으며 유기태(有機態) 질소(窒素), 아미노태(態) 질소(窒素) 및 acid hydrolysable는 균사생장(菌絲生長) 및 자실체(字實體) 발생기간중(發生期間中)에 현저(顯著)히 감소(減少)되었다. 7. 질소원(窒素源)을 달리하는 배지(培地)를 사용(使用)한 액체배양(液體培養)에서 peptone, yeast extracts 등(等)의 유기태(有機態)가 첨가(添加)된 배지(培地)에서는 균사생장(菌絲生長)이 촉진(促進)된 반면(反面) 무기태(無機態) 질소원(窒素源)이 첨가(添加)된 Richard' solution과 Czapek-dox solution에서는 균사생장(菌絲生長)이 저조(低調)하였다. 또한 유기태(有機態) 질소원(窒素源)의 함량(含量)이 높은 배지(培地)에서 균사생장(菌絲生長)이 더욱 양호(良好)하였다.

• Journal of Plant Biology
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• 제17권4호
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• pp.11-17
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• 1974

The present investigation dealt with observation and experiments concerning the growth and differentiation of hop plant, using the varieties of Cascade(C), Shinshuwase(Sh), and Hallertau(H). The results were as follows: (1) Life cycle of hop plants. The annual growth period of hop plant was devided chiefly into 3 phases, dormant, vegetative and reproductive. (2) Growth of main stem. The hop vine begun to grow in the middle of May and grow vigorousely in the middle and latter of June, then gradually decline or stops at the middle of July and the early of August. (3) Growth of lateral vines. By the statistical analysis, it is judged that the varieties of H and Sh were more grown than that of C. H and Sh were not significant, but H and Sh from C were significant in 5% level. (4) Fresh weight and water content of hop cone. Hop cone in fresh weight of C variety was higher than those of other two varieties and water content of hop cone was decreased with time elapse in three races together. (5) Growing point. Histological view of hop varities in each was different. C showed form of sweet potato, H showed form of round, and Sh showed form of ellipse. (6) Shape of the leaf. C and H were 3 lobes, but Sh is 3∼5 lobes. Generally, the color is dark green. (7) Hop cones. Hop cones are as follows.

• 한국임상수의학회지
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• 제34권2호
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• pp.126-131
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• 2017

This study investigated the incidence rate of umbilical hernia (UH) in pig farms and examined the effect of using them as breeding pigs on reproductive traits. The occurrence of UH ranged from 0.1% to 3.0% in pig farms investigated. UH pigs were found in almost all farms except for a single farm in Jeju Island. Spontaneously occurring UH pigs were selected and used for cross breeding tests. UH-related crosses and their progeny showed significant (P < 0.05) differences in gestation period, the numbers of piglets born and alive, and body weights at birth and $21^{st}$ day comparing to those of the control population. UH-related crosses showed longer gestation period, reduced numbers of piglets, and lighter body weights than those from the control population. Interestingly, reduced number of piglets was about one fourth, suggesting that UH inheritance might play a critical role as a lethal gene during embryogenesis. In addition, UH incidence rate in UH-related crosses was significantly (P < 0.05) higher than that in the control except for UH-cross3. However, in the progeny of control cross, a pig also had UH appearance, indicating that porcine UH might be inherited in recessive inheritance mode. Taken together, the results of this study indicate that UH is one of recessively inherited genetic defect that occurs at ordinary times in pig farms, suggesting that the use of UH animals as sire and/or dam may lead to economic losses due to increased gestation period, reduced numbers of piglets born and alive, and lower growth rates after birth of pigs.

• Journal of Ginseng Research
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• 제3권2호
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• pp.105-112
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• 1979

Effect of gibberllin on the breaking of bud dormancy of root and growth of aerial parts were investigated under laboratory and field condition for the prolongation of shoot growth duration, shortening of fruit bearing age and the increase of root yield. Drop application of GA (0.5ml of 50ppm) on rhizome of one year old root broke bud dormancy better than by low temperature. Soaking for one hour of one year old roots which wintered in the field in GA (50-200ppm) greatly accelerated the emergence of new buds while kinetin was only effective at low level (50ppm). GA substantially increased stem length in early stage and petiole length later on while kinetin increased stem diameter. Under the field condition with polythylene film tunnel (PET) in early spring the soaking in GA (50ppm for 1 hour) of rhizome of 4 year old root with replanting and dropping GA (50ppm, 1ml) on rhizome without replanting brought earlier emergence (29days) in comparison with that in the usual field. PET alone caused 14 day-early emergence. GA increased the length of stem and petiole only in early stage and replanting decreased only petiole length in later stage. Soaking in GA with replanting caused the Pronounced decrease in peduncle length, percentage of (ruin set and dry weight of reproductive organ (fruits and peduncle). Dropping without replanting showed significant decrease only in dry weight of reproductive organ. Fruit maturing was 20 days earlier than in usual held with little difference between GA and PET. It is well expected that GA could be used for early emergence of bud, shortening of root dormancy period, thinning of fruit and higher root yield according to application amount and methods.