• 한국환경보건학회지
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• 제9권2호
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• pp.11-17
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• 1983

The soil-transmitted helminthes, such as ascaris, whipworm, hookworm and trichostrongylus, have been considered as the most prevalent parasitic diseases in a matter of several decades ago in Korea. In facts, the attached eggs and/or larvae to the vegetables have been played a great role on the transmission to human because of raw eating the vegetables without the proper recipe. The aims of this study is to outline the attached helminthes egg in vegetables and to define whether the detection rates on them show a decreasing pattern or not in present. The subjected vegetables were collected from the three markets which are located at Goo-Pa Bal, Soo-Yoo Dong, Cheon-Ho Dong in suburban area, Seoul from April to May 1983. A total of 180 samples including such as 60 Korean cabbages, 60 young radishes and 60 Korean onions were examined. For the detection of helminthes eggs, the both methods of formalin-ether sedimentation and zinc-sulfate floatation were applied. The results were summarized as follows: 1) The detected eggs of ascaris, whipworm, hookworm, trichostrongylus and either filariform larvae or rhabditoidform larvae of hookworm, as well as unknown ones were found in vegetables subjected. 2) Out of 180 subjects, the overall detection rate showed 48 (26.7%). And in case of Korean onion, the rate revealed 22 heads (36.7%) among 60, 17 heads (28.3%) out of 60 Korean cabbages, 9 roots (15.0%) out of 60 young radishes respectively. 3) The ascaris eggs were detected 6 heads (10%) out of 60 Korean cabbages, while the filariform larvae of hookworm appeared in 7 heads (11.7%) among 60 Korean onions. 4) In the results of present study, the detection rates in vegetables were appeared to be the marked decreasing tendency as like 28.3%, 36.7%, 15% compared with 96%, 100%, 88% of previous investigators (Choi et al. 1967)each on Korean cabbage, Korean onion, young radish.

• 한국어류학회지
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• 제8권2호
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• pp.1-9
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• 1996

볼락속(屬)에 속하는 불볼락(Sebastes thompsoni)과 개볼락(S. pachycephalus pachycephalus)의 난형태(卵形態) 및 자어(仔魚)의 성장(成長)에 따른 형태발달(形態發達)에 대하여 관찰한 결과는 다음과 같다. 1. 불볼락과 개볼락의 수정난(受精卵)은 구형(球形)으로 무색투명하며, 불볼락의 난경(卵徑)은 1.27~1.33mm, 개볼락이 1.39~1.52mm였다. 2. 체내(體內)에서 부화(孵化)한 자어(仔魚)의 전진(全辰)은 불볼락이 3.02~3.12mm, 개볼락이 4.83~5.17mm였다. 3. 척색말단(脊色末端)이 $45^{\circ}$ 위로 굽어지는 시기는 불볼락이 전장(全長) 7.56~8.00mm, 개 볼락이 5.43~5.56mm였다. 4. 불볼락 자어(仔魚)는 흑색소포(黑色素胞)가 꼬리 중앙의 등쪽과 배쪽에 분포하는 점, 개볼락은 몸통의 중앙, 등쪽 및 배쪽에 밀집하여 분포하는 점에서 다른 종(種)과 구별된다. 5. 개볼락은 전장(全長) 14.22~15.86mm에서 등지느러미와 뒷지느러미 가시가 완전하게 형성됨으로써 변태(變態)가 일어나 성어(成魚)의 형태와 닮아 있다.

• 한국어류학회지
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• 제30권2호
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• pp.75-83
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• 2018

이 연구는 우리나라 고유종인 낙동납자루의 초기생활사를 연구하여 분류학적 연구의 기초자료로 이용하고자 한다. 낙동납자루는 수컷의 뒷지느러미 가장자리 검은색 띠가 짙고, 암컷의 산란관이 오렌지색을 띠는 것으로 알려져 있다. 난의 형태는 방추형이었고, 난경은(장경${\times}$단경) $4.41{\times}1.44mm$였다. 부화에 소요되는 시간은 수온 $21.0^{\circ}C$일 때 126시간이 소요되었다. 부화 직후의 자어는 난황을 가지고 있으며, 평균 전장은 $5.91{\pm}0.18mm$ (n=5)였다. 부화 후 18일째에는 꼬리지느러미가 발달하였고, 평균 전장은 $8.02{\pm}0.08mm$ (n=5)였다. 부화 후 41일째 자어는 난황을 대부분 흡수하였고, 평균 전장은 $8.70{\pm}0.23mm$ (n=5)였다. 부화 후 80일째 자어는 지느러미 기조 수가 정수에 달하였고, 평균 전장 $12.6{\pm}0.28mm$ (n=5)였다. 지느러미 기조 수는 등지느러미 ⅲ.8개, 뒷지느러미 ⅲ. 9~10개, 꼬리지느러미 19개, 측선비늘 수 32~35개로 어미와 유사하였다.

• 한국수산과학회지
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• 제37권6호
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• pp.485-491
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• 2004

Spawning induction, egg development and larval growth of ark shell (Tegillarca granosa) (L.) were investigated. The most effective method of spawning induction was steady temperature increasing from$4^{\circ}C\;to\;28^{\circ}C$ with irradiation of sea water by UV after T. granosa was exposed to air at $4^{\circ}C$ Optimum condition for larval roaring was under the 32.4 psu and two temperature $regimes:\;28{\pm}1^{\circ}C\;and \;25{\pm}1^{\circ}C$. Fertilized eggs was demersal isolated eggs, and egg diameter was $60{\mu}$. D-shaped larvae appear about 20 hr after hatching with $94.1{\mu}$ in shell length and $86.7{\mu}$ in shell height. Ten days were required from hatching to umbo larva stage, of a mean shell length $125.2{\mu}$. On 25th day, the larva grew to $450{\mu}$ in shell length and began to settle on the bottom. Effect of temperature between $25^{\circ}C$ (control group) and $28^{\circ}C$ on larval growth was not different. Survival rate of larvae settled on the bottom was about $19{\%}$ in both temperatures conditions $(25^{\circ}C\;and\;28^{\circ}C)$.

• 한국양식학회지
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• 제20권3호
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• pp.194-198
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• 2007

Reproductive traits of Palaemon gravieri such as embryo size, number of embryo (fecundity), incubation period, larval development mode, larval development period, larval survival and larval growth were described and compared to analyze the correlation among those traits. Embryo volume is a primary factor determining other ensuing reproductive features. Egg volume was $0.042mm^3$ in the first developmental stage. Embryo volume in P. gravieri was comparatively small which is indicative of great number of embryo (y = 3.0161x + 0.0185 $R^2$ = 0.74 positive isometric relationship) and relatively long incubation period. Larvae survived from zoea 1 to post-larvae and it took 45 days at $22^{\circ}C$. Survival rate of the larvae was rather great in the early stage and thereafter steadily decreased. Daily growth rate of larvae in P. gravieri at $22^{\circ}C$ was 0.0195 mm on average. They grew steadily as time went by. Incubation period was between 10-14 days at $22^{\circ}C$. Larval development mode was almost complete planktotrophic. PNR (point of no return) appeared to be the third day on average. Survival rate of larvae without feeding declined rapidly between 3 and 4 days. Larval development period and stage frequency were 23-30 days and 11 stages which imply prolonged larval period and high mortality. The pattern of brood production followed fast successive parturial pattern. Most ovigerous female had mature ovary when they performed parturial molt soon after hatching (larval release).

• 한국환경과학회지
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• 제29권7호
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• pp.789-792
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• 2020

The present study was investigated the oviposition characteristics of Protaetia brevitarsis seulensis with a focus on winter larvae to improve the utilization of insect resources. The average oviposition tendency and average cumulative number of eggs laid during a 7-week period were measured in adults emerging from larvae that had hibernated for 4 months in five farmhouses. The study covered five zones: Gimje, Jangsu, Wanju, Iksan and Yeoju. The average oviposition tendency over a 7-week period showed increased egg laying between 2 to 3 weeks and 5 to 6 weeks. Overall, it was found that the average cumulative number of eggs laid during the 7-week period was initially low and increased proportionally with time. Our results suggest that using adults that have emerged from hibernated larvae is effective in increasing the oviposition rate and utilization of the insect.

• Fisheries and Aquatic Sciences
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• 제17권1호
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• pp.137-143
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• 2014

The hairtail (currently recognized as Trichiurus lepturus in Korea) is one of the most important commercial fish species in Korea, Japan, China, and Taiwan. Because the amount of catches has been steadily declining, we must determine the early life stages of the hairtail from the viewpoint of resource management. Furthermore, the taxonomic status of the hairtail is unclear among ichthyologists, potentially creating management difficulties. Therefore, the purpose of this study was to compare morphological and molecular information on eggs, larvae, and adults of hairtail from Korea with that of T. lepturus from the Atlantic Ocean, and to review the taxonomic status of the hairtail. A total of 510 base pairs of the mitochondrial DNA cytochrome oxidase subunit I sequences of 12 eggs, 2 larvae, and 11 adults of the hairtail from the Korean waters clearly matched those of Trichiurus japonicus adults (d = 0.000-0.014) from the East China Sea rather than those of T. lepturus (d = 0.100-0.110) from the Atlantic Ocean. Our results also showed that larvae of the Korean hairtail are different than those in the Atlantic Ocean in having no melanophores along the ventral edge of the lower jaw. Therefore, our findings suggest that the hairtail in the Korean waters may not be T. lepturus, but T. japonicus.

• 한국발생생물학회지:발생과생식
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• 제22권4호
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• pp.361-367
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• 2018

The newborn, Hippocampus kuda larvae were 6.97-8.81, standard length (SL) mm (mean 7.89 mm) and mouth and anuse were open. Dorsal fin rays 15-18 and pectoral fin-rays were counted 8 and had 10-11+21 myotomes, body's bony plate ring being developed strongly in the central axis of myotomes part. 4 days after bearing, the SL was 7.02-9.47 mm (mean 8.24 mm) and nostrils began to open. 12 days after bearing, larvae attained to 8.91-11.2 SL mm (mean 10.0 mm). From this time, their unique predation habit appeared. 21 days bearing, larvae attained to 12.1-14.8 SL mm (mean 13.4 mm) the and thorn of back was enlarged among the plate formed around ring. 41 days bearing, seahorses attained to 17.1-17.8 SL mm (mean 17.4 mm) and the number of body's bony plate ring of the top of rings trunk was 11 and on the tail of them was 33-36, similar to figure of adult.

• 한국발생생물학회지:발생과생식
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• 제18권1호
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• pp.25-31
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• 2014

This study was investigated spawning behavior, structure of egg masses and egg development in Aplysia kurodai inhabiting the coastal waters of Jeju Island, Korea. The mating and courtship behavior of A. kurodai occurred in the form of unilateral copulating with chain formation. In chain copulation, only the first animal acted as a female; the second and succeeding animals acted as males (sperm donors) to the animals in front and as females to the animals behind. The fertilized eggs were packaged in capsules that are embedded in jelly to form a cylindrical string called an egg masses. The number of capsule per cm of the egg masses was 55 to 60 capsules and each capsule within the egg masses held 15 to 25 eggs. After spawning, the egg masses were bright yellow or orange in color. This egg masses color not changed until embryos developed into trochophore stage. Thereafter, as embryo developed from trochophore stage to veliger stage the egg masses color became brownish. The fertilized eggs were spherical, with a diameter of approximately $80{\pm}1{\mu}m$ at spawning. At 5 to 6 days after spawning, the embryo developed into trochophore stage and began to rotate within the egg capsule. In the trochophore stage, the precursor of the velum, called the prototroch or prevelum, developed. At 10 days after spawning, the prevelum is transformed into the velum, and the trochophore developed into veliger stage. Between 10 to 15 days after spawning, the veligers broke out of the egg capsule, and hatched as free-swimming larvae.

• 한국어류학회지
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• 제1권1_2호
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• pp.1-8
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• 1989

1989년(年) 8월(月), 경남(慶南) 진해만(鎭海灣), 자란만(紫蘭灣)에서 채포(採捕)된 성숙한 친어(親魚)를 사용한 수조내(水槽內)에서의 쑤기미의 난발생(卵發生) 및 부화자어(孵化仔魚)의 형태(形態)에 대한 관찰(觀察) 결과(結果)를 요약하면 다음과 같다. 1. 수정난(受精卵)은 직경이 1.2~1.3 mm인 분리부성난(分離浮性卵)으로, 유구(油球)가 없다. 수온(水溫) $24.9{\sim}26.5^{\circ}C$에서 E+26~29시간만에 부화하였다. 2. 부화직후(孵化直後) 자어(仔魚)는 전장(全長)이 2.47~3.10 mm였으며, 입과 항문(肛門)이 열리지 않으며, 몸 전체에 황색소포(黃色素胞)가 산재하여 있고, 난황(卵黃)을 위로하여 떠있다. 근절수(筋節數)는 13+16~17=29~30개였다. 3. 부화(孵化) 후(後) 2일째 전장(全長) 3.61~4.16 mm의 자어(仔魚)는 가슴지느러미가 부채형으로 크게 발달하여, 그 위에 3~4개의 커다란 흑색반점(黑色斑點)이 나타났다. 4. 부화(孵化) 3일째 전장(全長) 3.97~4.29 mm의 자어(仔魚)는 난황(卵黃)을 완전히 흡수하였으며, 가슴지느러미 줄기가 4~5개 발달하였다. 5. 부화(孵化) 6일째 자어(仔魚)는 전장(全長)이 4.07~5.46 mm 범위이며, 가슴지느러미에 11개의 줄기가 발달하였고, 흑색반점(黑色斑點)은 줄기끝부분에서 8~9개로 증가하였다.