• 대한수의학회지
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• 제15권2호
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• pp.177-180
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• 1975

This study was undertaken to obtain more detailed knowledge of the oxygen consumption rate of chick embryos, of the relationship between the increasing rate of embryo weight and that of oxygen consumption, of the daily increase of oxygen consumption by that of embryo weight, and of the metabolic rate of the White Leghorn eggs. The results obtained are summarized as follows. 1. The average oxygen consumption rate of the chicken embryo at the 3rd day of incubation is 0.8ml/h, STPD. It is strongly suggested that this value can used as a physiological criterion to classify the fertilized and unfertilized eggs, on the other hand oxygen consumption rate of the fertilized eggs reaches a plateau between the 18th and 20th days. 2. There exists a parallel relationship between the increasing rate of embryo weight and that of oxygen consumption rate during the incubation period. 3. There are not exist a parallel relationship between the daily increase of embryo weight and that of oxygen consumption during the whole incubation period. 4. The metabolic rate of chicken embryo(ml/h/g) is highest in the early stage of incubation and it started to decrease sharply until the 8th day follow by slow decrease thereafter.

• International Journal of Industrial Entomology and Biomaterials
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• 제13권2호
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• pp.63-72
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• 2006

Parthenogenesis, the development of unfertilized ovum opens new perspectives in silkworm breeding in the development of homozygous breeds. In order to improve induction of artificial parthenogenesis in the excised unfertilized eggs of different breeds of the silkworm, Bombyx mori L., a new method was devised and the results were compared with the routine method. General and specific combining abilities and hybrid vigour of newly developed bivoltine breeds were analyzed utilizing bivoltine breeds viz., $CSR_2,\;CSR_4,\;CSR_{17}\;and\;NB_4D_2$ Estimation of GCA revealed superiority of the breeds, $DNB_1$ for eight characters followed by $DNB_4$ for five characters. Among the testers, $CSR_2$ was found good general combiner for seven characters followed by $CSR_{17}$ for four characters. A great deal of variations was observed among the hybrids studied. Five hybrids namely, $DNB_1{\times}CSR_2,\;DNB_4{\times}CSR_4,\;DNB_4{\times}NB_4D_2,\;DNB_6{\times}CSR_2\;and\;DNB_7{\times}CSR_2$ showed significant SCA effects for 5-6 characters. The hybrid, $DNB_4{\times}CSR_4$ showed its superiority by expressing significant hybrid vigour over BPV for 7 characters. Majority of the hybrids exhibited significant hybrid vigour for survival rate, yield/10,000 larvae by weight, cocoon weight, cocoon shell weight, filament length and denier.

• 한국응용곤충학회지
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• 제22권4호
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• pp.262-270
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• 1983

온${\cdot}$습도가 벼멸구(Nilaparvata lugens stal)의 생육에 미치는 영향을 알아보기 위하여 30, 25, $20^{\circ}C$의 세 수준의 온도구 내에 습도를 95, 75, 65, $35\%$의 네 수준으로 하여 2세대까지 개체사육한 결과를 요약하면 다음과 같다. 1. $25^{\circ}C$에서 벼멸구의 발육과 비교해 볼 때 $30^{\circ}C$에서는 난기간, 약충기간, 성충수명이 단축되었고 약충의 사망률은 증가하였으며 산란수는 크게 감소하였다. 또한 산란된 난은 수정이 되지 않았거나 배자발육도중 죽음으로서 부화가 전혀 이루어지지 않았다. 2. $25^{\circ}C$와 비교하여 $20^{\circ}C$의 저온에서는 난과 약충 발육기간이 상당히 지연되었고 성충수명이 짧아졌으며 산란수가 크게 감소하였을 뿐 아니라 부화율도 감소하였다. 3. 약충의 치사율은 RH $75\%$ 이상의 비교적 높은 습도조건에서 높았으며 또한 다습조건에서는 성충의 수명이 단축된 결과 산란수가 크게 감소하였다.

• 한국가금학회지
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• 제30권2호
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• pp.91-94
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• 2003

본 시험은 육용종웅계의 원정액과 동결정액을 이용하여 인공수정시 종란의 수정율에 미치는 영향을 비교ㆍ조사하여 동결정액의 산업화 적용 가능성에 대한 기초자료를 제공 하고자 실시하였다. 5 수의 로스 육용종웅계에서 얻어진 정액을 원정액 및 동결정액으로 처리하여 각각 30 수 씩의 육용종빈계에 인공수정하였다. 종란은 정액처리당 총 180개를 입란하였으며, 입란 후 10 일째에 검란하여 수정율 및 발육중지율을,21일째 부화율을 조사하였다. 동결정액에 의한 수정율 및 부화율은 68.0 및 47.1％로 이는 원정액처리구의 88.3및 87.2％ 보다 유의하게 낮았다. 또한 동결정액을 이용하여 인공수정을 시켰을 때에 무수정란수는 원정액을 사용하였을 때 보다 2.7 배 유의적으로 높았으며 발생중지란수도 3.2배 높았다(P<0.05). 원정액과 비교하여 동결정액을 이용한 인공수정시 보여준 높은 무정란수와 발생중지란수를 개선하기 위한 더 많은 연구가 필요하다고 사료된다.

• 한국패류학회지
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• 제15권2호
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• pp.115-119
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• 1999

We investigated the processes of egg and larval developments for aquaculture technique development of seedling production fo the flat oyster, Ostrea denselamellosa. Teo flat oyster of larviparous type was different from the pacific oyser (ovivarous type) because their larvae (trochophore and prodissoconch larvae) in the gill released into the seawater. The process of egg development was observed by artificial fertilization at $25^{\circ}C$, using a dissecting method. The sizes of Unfertilized eggs ranged from 80 to 90 $\mu\textrm{m}$ and fertilized eggs with globule-shape was 90-100 $\mu\textrm{m}$. The Polar body appeared after fertilization and egg cleavage began within 1 hour, reaching the blastula stage after 10 hours. The trochophore in the gill appeared 2-3 days after fertilization and grew to the prodissoconch larvae (130 140 $\mu\textrm{m}$) having a complete shell after 1-2 days. The shell of prodissoconch larvae grew to 205 220 $\mu\textrm{m}$ after 10 hours, and then they became umbo stage larvae showing oval in shape. The velum of umbo stage larvae was degenerated about 17-20 days after fertilization and grew into a pediveliger with a developed foot, at this time, the shell length size was 320 360 $\mu\textrm{m}$.

• 한국수정란이식학회지
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• 제4권1호
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• pp.41-45
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• 1989

Total thirty of flushing were attempted on day 4 to 15 of estrus cycle with S heifers and 9 cows by nonsurgical method. The flushed or recovered rate among flushings was 86.7% (26/30) or 88.5% (23/26), respectively. There was no difference in the recovered rate between heifers (85.7%,6/7) and cows (89.5%, 17119). The embryo was recovered on day 4 to 15 of estrus cycle from the donors in natural heat without any technical difficulties.The I2FG Foley catheter used for pubertal heifers had sometimes plug in it with uterine mucus during flushing of uterine horn. But the problem could be overcomed by pumping the catherter with fluthing solution or by changing the catheter. Three normal embryos were recovered from 3 pubertal (10-11 month old) heifers. The rate of normal and abnormal eggs was 60.9% (14123) and 39.1% (9/23), respectively. The abnormal eggs were on degenerating except one unfertilized egg and were mostly recovered from heifers or cows flushed consecutively during the estrus cycle. The developmental states of normal embryos were l6-cells on day 5, 32-cells on day 6, compacted-morula on day 7, early-to expanded-blastocyst on day 8-to 9, and hatching-to hatched-blastocyst on day 10 to 11 of estrus cycle. The stage of embryos on day 8 to 10 showed varities among donors. On day 8 to 9 of estrus cycle hatching-blas tocyst was recovered from some donors.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2004년도 춘계학술발표대회
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• pp.283-283
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• 2004

The eggs of most animal species are surrounded by an extracellular matrix known as chorion, egg envelope, egg coat, or zona pellucida. Development of fish embryo usually takes several days in an aquatic environment. During embryonic development, the chorion must protect embryo from physical damage and microbial infection in the exposed aquatic environment. (omitted)

• The Korean Journal of Ecology
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• 제28권5호
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• pp.281-286
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• 2005

A. signifer의 성숙난은 타원형이며 동물극쪽이 볼록하게 부푼 모양이다. 수정란의 크기는 장경이 $2.19{\pm}0.014mm$, 단경이 $1.85{\pm}0.080mm$로 장경이 단경보다 긴 모양이며 유구(oil globe)는 관찰되지 않았다. A. signifer의 방사대(zona radiata)는 그물과 같이 규칙적인 섬유성 그물(fibrilar net)구조로 되어 있었으며, 외측구의 직경이 약 $2.5{\mu}m$정도이고 내측구는 약 $1.5\sim2{\mu}m$이었다. A. signifer의 수정란은 $20{\pm}1^{\circ}C$하에서 동물극쪽에서 배반엽이 일정한 각도로 기울어져 발생이 진행되었으며 49시간 만에 부화하였고, 부화후 21일이 경과하여 난황이 모두 흡수되었다.

• 대한수의학회지
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• 제38권2호
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• pp.280-289
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• 1998

Voltage-sensitive ion channels contribute to establishment of the cell excitablity and the generation of the cellular function. At hamster oocytes in the primitive stage during developing process, an inward current elicited by voltage pulses was found to be carried mainly by $Ca^{2+}$. Even at present, $Ca^{2+}$ channels serve as the most probable route to pass this inward current but there is no evidence of the presence of this channels in eggs. To date, both the characteristic properties and the physiological role in the early stage of development remain unclear. Here we examined the characteristic properties of the inward current and changes in this currents at unfertilized oocytes, fertilized zygotes and two-cell embryos using whole-cell voltage clamp technique. The inward current carried reportedly by $Ca^{2+}$ was remained following removing external $Ca^{2+}$ but completely abolished by further replacement of impermeants such as tetramethylammonium ion ($TMA^+$) or $choline^+$ instead of $[Na^+]_0$. Tetrodotoxin did not affect on this inward current remained at $[Ca^{2+}]_0$-free condition. Removal of $Na^+$ ion out of the experimental solution clearly decreased the current. After adding 2mM $Ca^{2+}$ to the $Na^+$-free media, the inward current was restored. Interestingly, this current carried by either $Ca^{2+}$ or $Na^+$ was decreased by the reduction of intracellular $Cl^-$ concentration, or by $Cl^-$ channel blockers such as niflumic acid, DIDS and SITS. When $Cl^-$ concentration was lowered without changes in other ionic components, this inward current was reduced. At fertilized oocytes and two-cell embryos, the inward current carried by $Ca^{2+}$ and $Na^+$ was severely reduced. Also $Cl^-$ component could not be observed. From these results, the inward current is composed of $Ca^{2+}$, $Na^+$ and $Cl^-$ component, suggesting that the channel carrying this inward current is not selective specifically to $Ca^{2+}$. During early stage of development, the voltage-sensitive ion current seems not to contribute essentially to the cell cleavage and differentiation. The loss of $Cl^-$ component after fertilization suggests that $Cl^-$ may play a role in maintaining the viability of unfertilized ova.

• 한국발생생물학회지:발생과생식
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• 제6권2호
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• pp.71-76
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• 2002

최첨단 연구로 성장하고 있는 해양생물공학 연구 중 염색체공학 연구의 배수체 조작, 성분화, 자성 발생, 형질전환 어류와 유전자 조작에 관한 최근의 연구 동향을 분석하고 향후 발전 방향에 관하여 살펴보았다. 배수체 연구 중 3배체 어류 생산 연구는 20여종의 어류들 중 무지개 송어와 메기가 물리적 충격을 이용한 실험법으로 산업적으로 이용 가능한 수준에 있다. 성분화를 포함한 약 15종의 고급 어종이 방사선 투사법에 의해 자성 발생 2배체를 생산 유도하였다. 형질전환 어류는 1985년 이래 약 40여종의 어류가 외래 유전자를 미세 조작이나 전기충격법에 의해 형질전환되고 있다. 최근에 역바이러스성 벡터들에 의한 외래 유전자를 이용한 형질전환 어류가 생산되었으며 이러한 형질전환 어류는 기초과학 육성은 물론 해양생물공학 연구의 발전이 기대되고 있다.