• Fisheries and Aquatic Sciences
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• 제1권1호
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• pp.82-93
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• 1998

Monthly changes of the gonad follicle index (GFI), reproductive cycle, egg-diameter composition, first sexual maturity of the Pacific oyster, Crassostrea gigas, were studied based on the samples which have been collected from the intertidal zone of Poryong west coast of Korea, from January to December, 1996. C. gigas, is dioecious, while a few individuals are alternatively hermaphroditic. Monthly variation of gonad follicle index (GFI) used for determination of spawning period, coincided with the reproductive cycle. GFI increased from April when seawater temperatures gradually increased and reached the maximum in May. And then, GFI sharply decreased from June to September due to spawning. Reproductive cycle of this species can be divided into five successive stages: in females, early active stage (March to April), late active stage (April to May), ripe stage (May to August), partially spawned stage (June to September) and spent/inactive stage (September to February); in males, early active stage (February to March), late active stage (April to May), ripe stage (May to September), partially spawned stage (June to September) and spent/ inactive stage (September to February). The diameter of fully mature eggs are approximately 50um. Spawning occurred from June to September, and two spawning peaks were observed in June and August when the seawater temperature was above $20^{\circ}C$. Percentages of the first sexual maturity of males of 20.1-25.0 mm in shell height were over $50\%$, while those of females of 25.1-30.0 mm in shell height were over $50\%$. All the males of > 30.1 mm and all the females of ^gt; 35.1 mm completed their first sexual maturity. The results suggest that C. gigas has a protandry phenomenon. Sex ratios of 919 oysters observed were 453 females $(49.29\%)$, 429 males $(46.68\%)$, 16 hermaphrodites $(1.74\%)$, and 21 indeterminate individuals $(2.29\%)$. In age class I, sex ratio of males were $64.00\%$, thus, a higher percentage than that of females. It was noted that $64.00\%$ of the young males (age class I) were more functional than females in age class I, but 2-3 year-old oysters showed higher percentage of females. Percentages of hemaphrodites in 2-3 year classes were relatively higher than those in other year classes. Histological pattern of hermaphrodites can be divided into two types: Type I (hermaphrodite having a number of newly formed developing oocytes on the oogenic tissues within a degenerating spermatogenic follicle after discharge of numerous spermatozoa) and Type II (hermaphrodite having two separate follicles in the same gonad).

• 한방비만학회지
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• 제12권1호
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• pp.9-19
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• 2012

Objectives This study was designed to find out the relationships between obesity and growth, skeletal maturity among children by analyzing body composition and bone age. Methods Subjects were composed of 577 children from six years to seventeen years of age, without any other diseases related to growth, were measured their body composition and bone age. Results As obesity index was increased, the RH-MPH(%) and skeletal maturity significantly was also increased. The RH-MPH(%) of the obesity group was significantly increased than that of normal weight group; the skeletal maturity was more increased in th obesity group. It means the recent height of obese children was more taller than that of inherited from the parents, while skeletal maturity of obese children was more rapidly progressing. The RH-MPH(%) was increased in children who revealed stage of second sexual character; skeletal maturity was decreased in children who developed secondary sexual character. Conclusions Obesity children might be taller than what it supposed to be. However, obesity could cause the increase of skeletal maturity. It means the growth plate of obese children has been closed early.

• Asian-Australasian Journal of Animal Sciences
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• 제24권6호
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• pp.781-790
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• 2011

The effects of seedtime and maturity stage on nutritive value of five maize stover varieties, including conventional maize (Kexiangyu 11, CM), fodder maize (Huqing 1, FM), high oil maize (Gaoyou 115, HOM), sweet maize (Kexiangtianyu 1, SM) and waxy maize (Kexiangluoyu 1, WM), were examined based on chemical composition, in vitro gas production and in situ incubation techniques. Maize stover was sampled at d 17 and d 30 after tasseling, and designated as maturity stage 1 and stage 2, respectively. The average dry matter (DM) organic matter (OM), crude protein (CP) and fiber contents were the greatest for HOM, SM and FM, respectively. CM had the highest in vitro organic matter disappearance (IVOMD) and volatile fatty acid (VFA) concentration. The highest ammonia nitrogen ($NH_3$-N) concentration in the incubation solution, and effective degradability of DM ($ED_{DM}$) and neutral detergent fiber ($ED_{NDF}$) were observed in SM. Advanced maturity stage increased (p<0.05) DM content, $ED_{DM}$ and $ED_{NDF}$, but decreased (p<0.05) OM and CP contents, and decreased (p<0.05) b and a+b values, IVOMD and molar proportion of valerate in the incubation solution for maize stover. Maize sown in summer had greater (p<0.05) OM content, but lower DM, CP, neutral detergent fiber (NDF) and acid detergent fiber (ADF) content compared with maize sown in spring. Maize sown in summer had greater (p<0.001) IVOMD, $NH_3$-N concentration in the incubation solution and $ED_{NDF}$, but lower (p<0.01) ratio of acetate to propionate compared to maize sown in spring. The interaction effect of variety${\times}$seedtime was observed running through almost all chemical composition, in vitro gas production parameters and in situ DM and NDF degradability. The overall results suggested that SM had the highest nutrient quality, and also indicated the possibility of selecting maize variety and seedtime for the utilization of maize stover in ruminants.

• 한국패류학회지
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• 제29권4호
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• pp.313-323
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• 2013

Gonad development, the reproductive cycle, first sexual maturty and size at 50% of group sexual maturity (the biological minimum size) of Gomphina (Macridiscus) veneriformis were investigated for clams collected from the coastal waters of Donghae City, the East Sea of Korea by histological, and morphometric analysis. Monthly variations of the gonad index showed a pattern similar to that of the reproductive cycle. The reproductive cycle with the gonad developmental stages in female and male G. (M.) veneriformis can be classified into five successive stages: early active stage (December to March), late active stage (March to June), ripe stage (June to July), partially spawned stage (June to August), and spent / inactive stage (September to December). The spawning period continued from June to August, with a peak between July and August when the seawater temperature exceeds $20^{\circ}C$. The percentages of first sexual maturities of female and male clams ranging from 25.1 to 30.0 mm were 56.3% in females and 61.1% in males, and for clams over 30.1 mm shell length, it was 100%. Shell lengths at 50% of group sexual maturity (biological minimum size, $RM_{50}$) were 27.71 mm in females and 26.31 mm in males. Because harvesting clams < 26.31 mm in shell length could potentially cause a drastic reduction in recruitment, a measure indicating a prohibitory fishing size should be taken for adequate fisheries management.

• Asian-Australasian Journal of Animal Sciences
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• 제17권2호
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• pp.228-236
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• 2004

Two varieties of alfalfa (Medicago sativa L cv. Pioneer and Beaver) and timothy (Phleum pratense L cv. Climax and Joliette), grown at different locations in Saskatchewan (Canada), were cut at three stages [1=one week before commercial cut (early bud for alfalfa; joint for timothy); 2=at commercial cut (late bud for alfalfa; pre-bloom head for timothy); 3=one week after commercial cut (early bloom for alfalfa; full head for timothy)]. The energy values of forages were determined using three approaches, including chemical (NRC 2001 formula) and biological approaches (standard in vitro and in situ assay). The objectives of this study were to determine the effects of forage variety and stage of maturity on energy values under the climate conditions of western Canada, and to investigate relationship between chemical (NRC 2001 formula) approach and biological approaches (in vitro and in situ assay) on prediction of energy values. The results showed that, in general, forage species (alfalfa vs. timothy) and cutting stage had profound impacts, but the varieties within each species (Pioneer vs. Beaver in alfalfa; Climax vs. Joliette in timothy) had minimal effects on energy values. As forage maturity increased, the energy contents behaved in a quadratic fashion, increasing at stage 2 and then significantly decreasing at stage 3. However, the prediction methods-chemical approach (NRC 2001 formula) and biological approaches (in vitro and in situ assay) had great influences on energy values. The highest predicted energy values were found by using the in situ approach, the lowest prediction value by using the NRC 2001 formula, and the intermediate values by the in vitro approach. The in situ results may be most accurate because it is closest to simulate animal condition. The energy values measured by biological approaches are not predictable by the chemical approach in this study, indicating that a refinement is needed in accurately predicting energy values.

• 한국식품과학회지
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• 제53권2호
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• pp.133-138
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• 2021

국내에서 재배한 A. melanocarpa 잎의 성숙도에 따른 이화학적 특성 변화, 항산화 물질 조성 변화 및 항산화 능력과 같은 기능적 특성을 분석하여, 아로니아 잎의 성숙도별 이용 가능성을 확인하였다. A. melanocarpa 3품종의 잎의 폴리페놀, 플라보노이드, 페놀화합물 함량은 성숙이 진행될수록 감소하였고, 항산화물질과 상관관계가 높은 ABTS 라디컬 소거능 및 DPPH 라디컬 소거능 역시 감소하는 경향을 보였다. 현재, 블루베리는 잎과 열매 모두 식품원료로 등록되어 있으나, 아로니아의 경우는 식품의약안전처에서 고시한 식품원료목록 상 열매 부위만 등록되어 있는 실정이다. 아로니아 잎에는 chlorogenic acid와 catechol이 다량 함유되어 있고, 아로니아 잎의 항산화 능력은 기타 베리류와 비교하였을 때, 상당히 높은 수준인 것으로 확인된 바와 같이, 아로니아 잎은 향후 가공 식품 이외에 다양한 분야로의 활용 가능성이 충분할 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권2호
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• pp.183-192
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• 2004

The effect of eight varieties of grain and forage type whole crop rice (Oryza sativa L Japonica) each harvested at four stages of maturity were investigated for morphology and yield, proportion of botanical fractions, fermentatability and chemical composition in an $8{\times}4$ factorial experiment. All crops were sown in 1997 at Saitama Prefecture, Japan under identical condition and harvested on 10, 22, 34 and 45 days after flowering in 1998. Total DM yield of forage type varieties was similar to that of the highest yield of grain type varieties. However, while yield of forage type varieties was attributed to higher proportion of straw than head, the reverse was in the case of grain type varieties. Yield in line with the proportion of head increased (p<0.001), but in contrast proportion of straw decreased (p<0.001) with the increase in maturity. Silage fermentability of grain type varieties was better than forage type varieties. Fermentability improved with the increase (p<0.001) in maturity suggesting that the moisture content should be reduced to improve fermentation quality. Forage type varieties contained higher (p<0.001) ash, crude fat (EE), organic cell wall (OCW) and acid detergent fiber (ADF), but contained lower crude protein (CP), organic cell content (OCC), CP in OCC and nitrogen-free cell wall extract (NCWFE) than the grain type varieties. The ash, CP, EE, Oa (60% digestible OCW), Ob (40% digestible OCW), OCW, ADF and acid detergent lignin (ADL) decreased (p<0.001), but OCC and NCWFE increased (p<0.001) with the increase in maturity. It is concluded that stage of maturity not only increases yield and proportion of head, but also improved the fermentation quality and increases quality chemical composition (except CP) of whole crop rice. Forage type varieties may be as good as grain type varieties in terms of yield, but fermentation quality and chemical composition may not be as good as that of grain type varieties.

• 한국초지조사료학회지
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• 제28권1호
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• pp.29-34
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• 2008

본 시험은 품종 및 수확시기가 총체 벼 사일리지의 품질에 미치는 영향을 구명하기 위하여 2004년부터 2005년까지 축산연구소에서 수행되었다. 식용벼인 추청벼와 총체 벼 전용품종인 하마사리를 이용하여 생육시기별로 6회(출수기, 개화기, 유숙기, 호숙기, 황숙기 및 완숙기)에 걸쳐 수확을 하여 사일리지로 조제하였다. 조단백질 함량은 숙기가 진행됨에 따라 감소되었으며 TDN 함량은 증가되었다. 평균 조단백질 함량은 총체 벼 전용품종이 식용벼 품종보다는 높게 나타났다. ADF 및 NDF 함량은 숙기가 진행됨에 따라 감소되었으며 ADF로 추정된 TDN 함량은 숙기가 진행됨에 따라 증가되었다. 그러나 품종간에는 통계적 유의성이 나타나지 않았다(p<0.05). 사일리지의 평균 pH는 4.69 이었으며 숙기가 진행됨에 따라 증가하였다. 생육이 진행됨에 따라 초산 및 낙산 함량은 감소되었으나 젖산 함량은 증가되었다. 품질등급은 호숙기에서 가장 우수하였다. 이상의 결과를 종합하여 볼때 총체 벼 사일리지는 전용 품종이 일반 벼 품종보다 약간 개선되는 것으로 나타났으나 유의적인 차이는 없었다. 따라서 양질의 총체 벼 사일리지 조제를 위해서는 호숙기 전후에 수확하여 사일리지를 만드는 것이 추천된다.

• Food Science and Biotechnology
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• 제15권1호
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• pp.44-50
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• 2006

Contents of phenolic compounds in peel, flesh, and core of three Asian pear cultivars, Hosui, Niitaka, and Chuwhangbae, were determined at different stages of maturity. Antioxidant properties of methanol extracts of peels at various fruit maturity stages were also evaluated. Total phenolic content decreased with maturity. Arbutin, chlorogenic acid, and epicatechin were major phenolic compounds in young fruits. Catechin, 4-hydroxymethyl benzoic acid, and caffeic acid were detected in peel and core of immature and mature pears. 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activities of methanol extracts were 16.30 and $15.73\;{\mu}g$ in peel of immature Hosui and Chuwhangbae pears, respectively, and $11.59\;{\mu}g$ in mature Niitaka pears, which was significantly higher than those of other maturity stage in the same cultivar. Inhibitory activities on lipid oxidation of methanol extracts of three cultivars at all maturity stages were similar to that of ${\alpha}$-tocopherol.

• 유기물자원화
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• 제17권4호
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• pp.36-47
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• 2009

유기물의 퇴비화과정중 미생물과 이에 관련된 퇴비의 생화학적 질량의 변화는 퇴비화공정 최적화와 최종산물의 품질은 매우 중요하다. 본 연구에서는 퇴비화단계중 미생물과 관련 생화학적 변수의 질량변화가 퇴비부숙도의 기준으로서의 적합성을 평가하였다. 전국 5개 퇴비공장 (용인축협, 양평축협, 논산축협, 전주연초, 지리산낙협)에서 세 단계 (초기, 부숙, 후숙)의 퇴비시료를 채취하여, Total Aerobic Bacteria(TAB), Coliforms, Escherichia coli, Actinomycetes, Fungi 등의 군집농도를 분석하였다. 연구결과, 5개 퇴비공장의 시료에서 Coliforms과 E.coli는 부숙단계에서 급격히 감소되어 후숙단계에서는 완전 사멸되었으나 다른 미생물은 완전 사멸되지 않았다. 그러므로 Coliforms과 E.coli 군집을 부숙도의 기준으로 제시하였다. 미생물탄소질량/질소질량비 (MBC/MBN)는 부숙단계에서 약간 감소하였으며, 후숙 단계에서는 증가하였다. 이는 부숙단계에서 Coliforms, E. coli, Fungi 등의 군집감소 때문으로, 후숙단계에서는 Fungi 및 TAB 군집증가 때문으로 이해된다. 또한 중금속성분 농도는 방선균 군집과 매우 강한 음(陰)의 상관성을 나타내었다. 본 연구의 성과는 Coliforms과 E.coli 군집 농도를 퇴비부숙도 기준으로 제시하였으며, 중금속농도와 미생물군집농도 상관관계를 이용하여 퇴비품질의 평가기준을 제시한 데 있다.