• Korean Journal of Environmental Biology
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• v.38 no.2
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• pp.323-331
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• 2020

The method of natural spawning is very passive and inconvenient for the study of developmental engineering in marine medaka, Oryzias dancena. The optimum concentration of human chorionic gonadotropin (HCG) and carp pituitary extract (CPE) for ovulation and spawning, and the injection time for the artificial spawning of marine medaka were analyzed in this study. The success rate, survival rate, and hatching rate were highest with 100IU HCG kg^-1 BW and 5mg CPE L^-1 in both male and female marine medaka (p<0.05). After obtaining unfertilized eggs and sperm by the injection of HCG and CPE into the broodstock of marine medaka, artificial fertilization could be successfully achieved any time fertilized eggs are needed in this species. This result should be useful for developing a study program for marine medaka as an experimental animal.

• Korean journal of applied entomology
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• v.36 no.4
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• pp.323-330
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• 1997

The apple leafminer, Phyllonorycrer ringoniella (Lepidoptera: Gracillariidae), is the most important pest on apple leaves and is not easy to be controlled with insecticides because of leafmining habit of its larvae. This study was undertaken to develop an artificial diet for mass rearing of the moth, and to look at their reproductive behavior. For developing an artificial diet the problem of diet contamination with microorganisms and how to supply artificial diet to first instar larvae have to be solved first. Artificial oviposition trial was successful with shadowy bottomside of various papers sprayed with apple leaf extracts. The highest activity of both calling and mating was observed within 30 min. after the onset of photophase and 3- to 4-day -old adults showed the highest mating rate. A ring-shaped sex pheromone gland was found at the intersegmental membrane between the 8th and 9th abdominal segments of the female. (E, 2)-4,lOtetradecadienyl acetate was identified as the major component from the femall gland extracts by the gas chromatography (GC) and GC-mass spectrometry. Additionally it was thought that (a-10-tetradecenyl acetate could be the second component of their sex pheromone.

• Journal of the korean veterinary medical association
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• v.34 no.8
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• pp.547-550
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• 1998

수의사들은 수캐와 고양이를 구입하기전 수캐의 번식력에 대한 검사를 요청 받을 때가 가끔 있다. 미국의 경우 Kennel club 지침에서는 7개월 보다 어린 개 또는 12세 이상된 개를 종견으로 등록할때는 번식력에 대한 소견서 혹은 증명서를 제출하여야만 한다고 되어있다. 번식력 검사에는 수캐의 완전한 병력을 수집해야하며 병력으로 과거 상처, 질병, 예방접종, 투약상태, 고환이 음낭으로 하강한 상태, 년령, 음낭부종 또는 외상의 발생상태 등이 포함되어야한다. 또한 애완동물의 가계에 대한 번식력에 대해서도 찾아보도록 노력해야 한다. 환축을 검사하기전 병력을 축주에 문의하는 것도 하나의 좋은 방법이다. 건강한 수컷이 암캐와 교미를 하지 못할 경우에는 번식관리의 검사에 세심한 주의를 기우려야 한다. 또한 산자의 최종출생일, 산자수, 교미회수, 번식시킨 암컷의 수, 교미형태, 수컷의 성욕 및 승가행위 등에 과한 것들을 조사해야 할 것이다. 이러한 병력으로 수컷은 항상 불임성을 최초에 불임성을 보였는지 또는 저임성을 보였는지를 알수있게 된다. 새끼를 낳아보지 못한 개와 고양이는 선천적으로 불임이 되고 이러한 수컷도 예후는 불량하다. 개와 고양이가 과거에 새끼를 임신한 경험이 없다면 생식기의 전염성 또는 염증과 관련이 있을 수도 있다. 축주는 개 인공수정을 하기 위하여 정액을 채취할 때 물, 소독약 및 윤활제 등으로 인하여 정자의 사멸을 의식하지 못하고 있기 때문에 채취방법을 상세하게 설명하여 주어야 한다. 또한 암컷의 번식문제에 대해서도 상세하게 검사하여야 하며 개와 고양이가 불임되는 가장 흔한 이유는 번식관리에 문제점이 있으며, 이와 같은 경우에는 암컷을 검사하기 전에 수컷을 검사하는 것이 중요하다. 수컷의 검사는 사진으로도 용이하므로 비용도 절감되나 암컷은 생식기관을 검사하여야 되기 때문에 많은 경비가 든다. 그러나 번식력의 유일한 증거는 태아를 생산하는 것이며 많은 다른 검사 방법으로 평가 할 수도 있으나 번식력을 증명할 수는 없다.

• Journal of Aquaculture
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• v.10 no.1
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• pp.17-24
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• 1997

In order to understand the spawning and larval development of Perinereis aibuhitensis for the effective seedling production, the influence of water temperature on spawning induction, egg and larval development of the worm were investigated from October 30, 1989 to October 30, 1990. Main spawning period was from July through September, and average diameter of mature eggs was $220\mu m$. The relationship between the adult weight (Wt) and the number of spawned eggs (NS) was given as follws : NS=48635.589Wt1.3044 (r=0.8572). Adult males and females died immediately after spawning. Trochophore larvae developed 12 hours after fertilization, and hatched out after 56 hours.

• Journal of Aquaculture
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• v.19 no.3
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• pp.166-172
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• 2006

Induced androgenesis, a form of artificial parthenogenesis is an important tool for the generation and use of genetically isogenic or clonal fish strain. An optimized protocol for the genetic inactivation of mud loach (Misgurnus mizolepis) oocytes (i.e. production of androgenetic haploid) was developed using UV-irradiation. Various dose levels of UV significantly affected the fertilizing capacity of the eggs, hatchability of embryos and incidence of haploidy. Based on the extensive examinations of treatment conditions on embryo viability and haploid incidence, the optimum dose level of UV irradiation was turned out to be $10,800ergs/mm^2$ with 56.9% of hatching success and 94.6% of haploidy. The overall yield of putative androgen under optimized treatment condition was more than 50% out of total eggs inseminated. The success of androgenetic reproduction of haploid genome was verified by flow cytometry and PCR amplification of transgene that is exclusive to either one of parental sexes. However, a small portion $(8\sim11%)$ of presumed androgenetic haploid larvae was proven to contain residual DNA fragment(s) from maternal parent.

• Parasites, Hosts and Diseases
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• v.28 no.1
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• pp.53-62
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• 1990

The growth and developmental pattern of H. continua was observed after experimental infection of their metacercariae to chicks. The recovery rate of worms from the chicks at 1 to 28 days post-infection(PI) was 12.8% in average. The rate remained fairly high for early 4 days of infection but decreased thereafter rapidly till 28 days PI. Most of the nukes, 91.9%, were recovered from the ileum of the chicks. In metacercariae, genital organs such as the ovary, testes, seminal vesicle, seminal receptacle and genital sucker were recognizable. At one day PI Mehlis'gland appeared, and at 2 days follicular vitellaria were observed. At 3 days PI, eggs were formed in the uterine tubule and increased in number as the worm grew old. The worms reached $2,990{\;}{\mu\textrm{m}}$ in length and $525{\;}{\mu\textrm{m}}$ in width at 28 days PI. Genital organs developed rapidly in early stages of infection but slowly thereafter to 28 days Pl, whereas non-genital organs developed steadily through the infection period. It was proved by this experiment that chicks should be a moderately suitable final host of H. continua.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.614-620
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• 2002

The sea bass, Lateoiabrax japonicus is a highly valued fish in aquaculture in South Korea. For establishment of seedling production of sea bass,1 japonicus, we examined change of gonadal development and plasma steroid levels of sea bass reared in indoor tank. Male matured unsimultaneously faster than females and spawning of females took place between the end of January and March. After the spawning period, and until the following January, all the females were in preyitello genesis and in some males, spermatogenetic activity restarted gradually. In October, under reducing photoperiod, cortical alveoli appeared in growing oocyte and the development of spermatogenesis greatly increased. Between October and february, vitellogenesis and spermatogenesis occurred respectively in female and male and gonadosomatic index increased from 4.31 to $24.07\%$ in female and upper 6o/o in male. Also, two sex hormones were analyzed during the course of a reproductive cycle in the sea bass: plasma levels of the gonadal steroid testosterone (T) and estradiol-l7$\beta$ (E_{2}). Variation of the plasma concentrations of T and E, appeared to depend on gonad stages. Plasma T and E, levels were high from November to January, suggesting that an sufficient gonadal stimulation by both hormones may undergoing a processes for the formation of sperm and oocyte.

• Korean journal of applied entomology
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• v.57 no.4
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• pp.287-295
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• 2018

A meridic artificial diet, including whole milk powder, wheat bran, maize leaf powder, and sucrose as the main nutrients, was tested for rearing Locusta migratoria (Orthoptera: Acrididae). When locusts were supplied with only the artificial diet over their entire life cycle, a second generation was not produced. The same result was observed when the diet was supplied daily and fresh maize leaves were supplied every other day. However, when the diet and fresh maize leaves were supplied alternately every other day, four generations of L. migratoria were produced. Fecundity in adults reared with the alternating diet was higher than that in adults supplied with both the diet and maize leaves daily. These results indicate that this artificial diet could be used as a supplementary food for rearing of L. migratoria.

• Journal of Yeungnam Medical Science
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• v.16 no.1
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• pp.131-136
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• 1999

자궁경관 임신은 최근에 인공유산의 증가와 인공 보조 생식술(assisted reproductive technology) 등에 의하여 증가되는 양상을 보인다. 과거에는 자궁경관 임신은 대량의 무통성 질출혈로 진단을 내리고 치료 방법은 천자궁적출술이 유일한 수단이었으나, 지금은 질식 초음파의 개발로 자궁경관 임신을 조기에 진단하고 자궁 보존적 방법으로 치료하여 차후 임신을 기대할 수 있게 되었다. 그 치료 방법 중 하나로 Methotrexate(MTX)를 주사하여 성공적으로 치유된 많은 보고들이 있었다. 본 저자들은 임신 8주에 자궁경관 임신으로 진단된 환자에서 전신적 MTX 투여와 복식 초음파 관찰 하에 양막강내 MTX 투여 병합 요법으로 치료한 1례를 보고하고 치료과정에서 자궁경부 병변의 지연 관해에 대해서 문헌 고찰과 함께 보고하는 바이다.

• Journal of the korean veterinary medical association
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• v.38 no.7
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• pp.612-619
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• 2002

최근 가축을 사육하고 있는 현장에서 번식장애 즉 불임증을 호소하는 농가들이 예전에 비해 부쩍 늘어가고 있는 추세에 발맞추어 임상수의사들이나, 인공수정업무를 행하고 있는 인공수정사, 사육농가들이 번식장애를 예방 또는 치료의 목적으로 호르몬 제재를 사용하거나 번식효율을 제고하고 저 이를 사용하고 있는 경우가 허다하게 볼 수가 있다. 허나, 이러한 호르몬 제재들의 그 유효성분, 적용 축종, 투여방법, 안전성 및 부작용 등을 정확하게 숙지한 상황에서 사용하지 않으면 오히려 호르몬 제재의 오, 남용으로 인한 번식장애를 유발할 가능성이 높다고 하겠다. 필자 역시 전국각지에서 가축들을 사육하고 있는 농가들이 방문 내지는 인터넷, 전화 등의 유선통신로부터 많은 질문을 받아온 결과 상당히 많은 분들이 정확한 진단이나 지식이 없이 무분별하게 사용하고 있는 실태를 보고 경악을 금치 못했던 기억을 새삼 떠올려짐을 어찌할수 없음을 밝혀둔다. 따라서 우리 임상전문수의사들의 생식기검사가 이뤄진 후 정확한 진단하에서 사용되고 있는 호르몬 제재는 기술(旣述)한 바와 같이 별반 문제점이 발생할 소지가 적으나, 이외의 비전문가들이 사용하는 경우는 오히려 호르몬제재를 사용하지 않는 경우보다도 나쁜 악영향을 초래할 가능성이 높다고 하겠다. 이에 우리임상전문수의사 뿐만 아니라 수의관계업무에 관련하는 모든분들에게도 최근 호르몬 및 그 제재에 대한 정확한 지식을 숙지하여 나갈 필요성을 절감하여 이에 대해 상세한 고찰을 하여 나갈까 한다. 이 글을 읽어보는 수의사들에게 조그마한 도움이 되었으면 하는 바램을 피력하고 싶다.