• Korean Journal of Animal Reproduction
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• v.21 no.1
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• pp.71-78
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• 1997

This study was conducted to investigate the activation condition of freshly matured bovine IVM oocytes for use as a cytoplasmic recipient in nuclear transfer. Bovine oocytes matured in vitro for 22-24 h were treated with various activation conditions. In Experiment 1 in vitro matured oocytes were treated with electric stimuIus (ES; 2 pulses of 1.25 kV/cm for 70 ${\mu}{\textrm{s}}$ec, each pulse 1 sec apart), ethanol (ET; 7%, 5min) , Ca$^2+$-ionophore(A23187; 10$\mu\textrm{g}$/ml, 5min) and cycloheximide(CH; 10$\mu\textrm{g}$/ml, 6 h). Activation rates were similar in treatments with ES, ET and A23187(48.8~54.3%), however, significantly reduced with CH treatment(15.9%, P

• Korean journal of applied entomology
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• v.55 no.2
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• pp.149-160
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• 2016

Temperature-dependent development and fecundity of apterious Rhopalosiphum padi (L.) (Hemiptera: Aphididae) were examined at six constant temperatures (10, 15, 20, 25, 30 and $35{\pm}1.0^{\circ}C$, RH 50-70%, 16L:8D). Development time of nymphs decreased with increasing temperature and ranged from 42.9 days at $10^{\circ}C$ to 4.7 days at $30^{\circ}C$. The nymphs did not develop until adult at $35^{\circ}C$ because the nymphs died during the 2nd instar. The lower threshold temperature and thermal constant of nymph were estimated as $8.3^{\circ}C$ and 101.6 degree days, respectively. The relationships between development rates of nymph and temperatures were well described by the nonlinear model of Lactin 2. The distribution of development times of each stage was successfully fitted to the Weibull function. The longevity of apterious adults decreased with increasing temperature ranging from 24.0 days at $15^{\circ}C$ to 4.3 days at $30^{\circ}C$, with abnormally short longevity of 11.1 days at $10^{\circ}C$. R. padi showed the highest fecundity at $20^{\circ}C$ (38.2) and the lowest fecundity at $10^{\circ}C$ (3.9). In this study, we provided component sub-models for the oviposition model of R. padi: total fecundity, age-specific cumulative oviposition rate, and age-specific survival rate as well as adult aging rate based on the adult physiological age.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.387-394
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• 2013

The developmental times of mealworm beetle larvae, Tenebrio molitor were studied at six temperatures ranging from 15 to $30^{\circ}C$ with 60~70% RH, and a photoperiod of 14L:10D. Mortality of larval period was very low at 17 and $20^{\circ}C$ but did not die over $22^{\circ}C$. Developmental time of larva was decreased with increasing temperature. The total developmental time of T. molitor larvae was longest at $17^{\circ}C$ (244.3 days) and shortest at $30^{\circ}C$ (110.8 days). Egg and larvae were not developed at $15^{\circ}C$. The lower developmental threshold and effective accumulative temperatures for the total larval stages were $6.0^{\circ}C$ and 2564.1 degree-days, respectively. The relationship between developmental rate and temperature was fitted by a linear model and nonlinear model of Logan-6($r^2$=0.95). The distribution of completion of each development stage was well described by the 2-parameter Weibull function ($r^2$=0.8502~0.9390).

• Journal of Sericultural and Entomological Science
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• v.33 no.1
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• pp.1-5
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• 1991

PBS soluble- and insoluble-extracts form silkworm eggs were analysed by native-PAGE and SDS-PAGE. During the embroyonic development, soluble proteins which are mainly composed of ESP, vitellin and 30K proteins showed similar degradation pattern in both electrophoretic analyses. Several peptides which seemed to be intermediated forms of yolk proteins were detected in latter part of embryogenesis, while a protein band newly appeared in one day elapsed after acid treatment. When insoluble extracts from silkworm eggs were analysed with SDS-PAGE, several peptides were detected at the later stages of the embryonic development, and newly hatched larvae. These peptides are considered to be structure proteins for embryonic morphogenesis.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.287-292
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• 2005

The soybean varieties the bean bug preferred the least were Kwangankong, Namhaekong, Sunamkong, Sorogkong, and Anpyeongkong, and next to them was Pungsannamulkong, among 25 varieties examined. Myongjunamulkong and Eunhakong supported a good growth of the bug as the daily gains of weight of 3rd instar nymphs were 14,9 and 13.9 mg, respectively. On the other hand the bug on Punsannamulkong gained weight daily as little as 10.1 mg. On Pungsannamulkong the nymphal development of the bean bug took $24.5{\pm}2.1$ days, about three days longer than those on Myunjunamulkong and Eunhakong. The survival of the bean bug on Punsannamulkong was 83%, slightly lower than those on Myunjunarnulkong and Eunhakong. It seemed evident that Pungsannamulkong have a non-preference type resistance to the bean bug.

• Korean Journal of Animal Reproduction
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• v.24 no.3
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• pp.263-268
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• 2000

The development of single blastomeres isolated from 2-, 4- and 8-cell mouse embryos and the ability of such blastomeres to survive slow freezing were studied. Of 223, 60 and 188 single blastomeres isolated from 2-, 4- and 8-cell mouse embryos, respectively, 111 blastomeres (49.8%) from 2-cell embryos, 12 blastomeres (20.0%) from 4-cell embryos and blastomeres (16.5) from 8-cell embryos developed into blastocysts after culture for 96 hrs. The recovery rate was 54.2% (65/120), 46.4% (13/28) and 24.3% (17/70) of blastomeres derived from 2-, 4- and 8-cell embryos following freezing and thawing and the survival of frozen-thawed blastomeres was 27.1% (16/59), 36.4% (4/11) and 17.6% (3/17), and respectively. The apparently six normal fetuses were obtained from frozen-thawed blastomere from 2-cell embryos after transferring into the recipients. These results indicate that mouse btastomeres isolated from preimplatation stage embryos can survive storage in liquid nitrogen following slow freezing.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2003.10a
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• pp.149-149
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• 2003

• Korean journal of applied entomology
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• v.55 no.2
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• pp.119-128
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• 2016

This study was conducted to develop temperature-driven models for a population model of turnip aphid, Lipaphis erysimi: nymphal development rate models and apterious adult's oviposition (larviparous) model. Nymphal development and the longevity and fecundity of adults were examined on cabbage at six constant temperatures (10, 15, 20, 25, 30, $35{\pm}1^{\circ}C$, 16L:8D). L. erysimi nymphs did not survive at $10^{\circ}C$. Development time of nymphs increased with increasing temperature up to $30^{\circ}C$ and thereafter slightly decreased, ranging from 18.5 d at $15^{\circ}C$ to 5.9 d at $30^{\circ}C$. The lower threshold temperature and thermal constant were estimated as $7.9^{\circ}C$ and 126.3 degree days, respectively. The nonlinear model of Lactin 2 fitted well for the relationship between the development rate and temperature of small (1+2 instar), large (3+4 instar) and total nymph (all instars). The Weibull function provided a good fit for the distribution of development times of each stage. Temperature affected the longevity and fecundity of L. erysimi. Adult longevity decreased as the temperature increased and ranged from 24.4 d at $20^{\circ}C$ to 16.4 d at $30.0^{\circ}C$ with abnormal longevity 18.2 d at $15^{\circ}C$, which was used to estimate adult aging rate model for the calculation of adult physiological age. L. erysimi showed a maximum fecundity of 91.6 eggs per female at $20^{\circ}C$. In this study, we provided three temperature-dependent components for an oviposition model of L. erysimi: total fecundity, age-specific cumulative oviposition rate, and age-specific survival rate.

• Korean Journal of Poultry Science
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• v.29 no.2
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• pp.89-94
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• 2002

This study was performed to evaluate effects of different holding temperatures and storing periods during the pre-incubation period on egg hatchability of hens egg in broiler breeders. For the treatments 1(T1)~7(T7), which were stored fur 1(T1) to 7 days(T7) before egg incubation, respectively. There were three replicates per treatment and forty eggs per replicate. This study was performed twice, which were 40(Summer) and 50 weeks of age(Autumn) in broiler breeders. Storing ambient temperature of egg, egg weight, at 0 and 18 days during incubation, fertility, hatchability and embryo mortality were examined. Average hatchability was rapidly decreased only in Summer. Although it was not significantly different in Autumn. This experiment was concluded that storing periods of hatchery egg was influenced hatchability, especially in high ambient temperature conditions(Summer, above $25^{\circ}C$ ). In conclusion, we found out that optimum hatchability can be achieved with a storage temperature of 13 ~$19^{\circ}C$ for broiler breeder eggs stored for up to 7 days.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.393-400
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• 2010

The parasitism, development time, hatchability, and progeny production of Trichogramma chilonis(TC) females developed in eggs of Helicoverpa assulta (HAs), Cadra cautella (CC), and Helicoverpa armigera (HAr), respectively, were compared with those developed in reciprocal eggs at constant temperatures of $25{\pm}2^{\circ}C$ and relative humidity of 50~70% under 16L-8D. Developmental performances of TC reared in each of the three hosts on the following hosts(host tested) appeared differently, and were affected most by the size of the proceeding hosts and test host. Among the parameters parasitism and progeny production were affected more than others. Parasitism was significantly different between the treatments, lowest in CC-HAr($10.1{\pm}2.05%$) and highest in HAr-HAs($47.0{\pm}2.09%$), and the hatchability showed similar pattern. Development time as well was shortest in the CC-HAr where previous host is smallest and test host is biggest. The highest number of progeny production of TC was observed in HAr-HAs($93.9{\pm}6.87$ wasps), and the lowest was CC-HAs($18.4{\pm}6.36$ wasps).