• The Korean Journal of Zoology
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• v.5 no.1
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• pp.30-34
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• 1962

For the purposeof examining DDT influences to fruit-filies, Drosophila Melanogaster , authors observed the number of eggs laid and hatching rate of them treated with various concentrations of DDT. The results obtained were summarized as follows : 1. There was a significant difference between treated and non-treated groups in the number of eggs laid. 2. The number of eggs laid in the treated groups was gradually decreased as the DDT-concentration increases. 3. The hatching rate of the treated larvae was not significantly different from that of the non-treated , while a distinct difference between treated group and non-treated one was seen when DDT treatment was given to the adults. 4. The average number of eggs laid by a non-treated fly for 15 days was 216. The curves for the number of eggs laid in both the treated and non-treated groups for 15 days revealed almost similar patterns, although the treated groups laid the largest : number of eggs in the forth day, while in the non-treated one it is seen in the sixth day after counting eggs.

• Journal of Sericultural and Entomological Science
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• v.39 no.1
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• pp.17-21
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• 1997

Oral application of fenoxycarb, O-ethyl N-(2-(4-phenoxyphenoxy)ethyl) carbamate, the commercial formulation Insegar, on the 1st day of the 3rd instar made no difference in the egg laying and the hatchability as compared to 750 grains for the number of eggs laid, 53 grains for the number of the resideual eggs unlaid, 749 grains for the number of fertirized eggs, 97% for the total hatchability, and 95% for the useful hatchability as in the control but on the first day of the 4th instar, the number of the remainder eggs in the ovary increased by 2.4 folds, and reduced number of the eggs laid, number of unfertilized eggs, the hatchabillity and useful hatchability by 39%, by 66%, by 68% and by 72%, respectively. When diluted Insegar was applied topically every other two days from the pupae to the moth at concentration of 10-6, 10-7, 10-8, 10-9, 10-10 the number of eggs laid, the number of the unfertilized eggs, the total hatchability and the useful hatchability were decreased. More severe decrease took place as concentration lowered and the earlier application.

• Journal of Environmental Science International
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• v.29 no.9
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• pp.935-938
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• 2020

This study investigated the oviposition characteristics of Protaetia brevitarsis seulensis after emergence as adults from the larva collected from three regions in Gangwon-do, Chungcheongnam-do, and Jeju-do. The laying egg method was identified with zone breeding, and the average and cumulative number of eggs laid were measured once a week for seven weeks. The average number of eggs laid peaked until 4 weeks, and subsequently decreased. The source areas with respect to average number and cumulative number of eggs laid were in the order of Jeju > Chungnam > Gangwon. In conclusion, this result suggests a method for continuously improving management and economic feasibility of insect farming by securing genetic diversity, and raising the most productive breeds to select individuals form regions associated with high numbers of laid eggs.

• Journal of Embryo Transfer
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• v.7 no.2
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• pp.89-96
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• 1992

This research was conducted to investigate the interrelationship among methods of injection of PMSG-hCG to the number of ovulated eggs, percentage of matured oocytes and in vitro fertilization using out-bred ICR mice. The results obtained are as follows, 1) The optimurn dose was 5 IU for both PMSG and hCG, while the number of ovulated eggs was 42$\pm$8, percentage of M II was 73% and in vitro fertilization rate was 81 %. 2) The optimum injection interval of PMSG-hCG was 48 hours, while the number of ovulated eggs was 48 $\pm$ 8, percentage of M II was 80% and in vitro fertilization rate was 81%. 3) The optimum time for collecting eggs was between 16 and 18 hours after hCG injection, while the numbers of ovulated eggs were 44$\pm$8, 42$\pm$7 and 43$\pm$7 in 14,16 and 18 hours after hCG injection respectively, and percentages of M II were 79 and 81 %, and in vitro fertilization rates were 81 and 80% in 16 and 18 hours after hCG injection, respectively. 4) The repeat of superovulation decreased with the number of ovulated eggs, percentage of M II and in vitro fertilization rate, than in control. But it was recovered by increasing the repeat interval.

• Journal of Preventive Medicine and Public Health
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• v.4 no.1
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• pp.35-39
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• 1971

The authors examined the Ascaris eggs on the surface of the strawberries and in the soil of the strawberry yards. The results were as follows: 1. The number of Ascaris eggs detected from 870 strawberries grown on strawberry yards was 26, of which 17 eggs were found to be alive. 2. The mean number of Ascaris eggs detected in every 10gm of the soil of strawberry yards was 10.3. The Ascaris eggs were detected over 93% from the yards examined, which had been fertilized with both chemical fertilizer and night soil, or night soil only. 3. No Ascaris eggs was found from strawberries which were produced only with chemical fertilizer. 4. Ascaris eggs were detected 6 from 705 marketing strawberries studied, 3 of them developed to larval stage. 5. when the strawberries were washed by shaking 20 times after kept immersed in water for 10 minutes, the recovery rates of Ascaris eggs after first, 2nd, 3rd, 4th and 5th washing were 60, 87, 96, 99 and 100%, respectively. 6. Besides Ascaris eggs of hook worm and Fasciolidae were also found from the strawberries examined.

• Ocean and Polar Research
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• v.24 no.4
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• pp.443-448
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• 2002

A study on the ichthyoplankton assemblage was conducted around Dokdo in the East Sea in September 1999 and May 2000. Sixteen species of fish larvae including eggs were collected during the surveys. Anchovy (Engraulis japonicus) eggs and larvae were comprised of 2.0% and 94.5% of total samples in number, respectively. Muller's pearlside (Maurolicus muelleri) eggs and larvae were comprised of 95.0% and 3.2%, respectively. The other species mostly composed of warm water species were less than 2% of total samples in number. The number of species and abundance of the fish lawae and eggs were higher in September than in May. Although there were limited data on the ichthyoplankton around Dokdo in summer and winter, this study area seems to be used for the spawning or nursery ground of fishes.

• Journal of Sericultural and Entomological Science
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• v.6
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• pp.53-56
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• 1966

1. On the contrary to the general insect size, male is larger than female. 2. The possible number of eggs, the maximum number of eggs per a morh is average 225 eggs. 3. The periods of the eggs laid is around 3 days. 4. The growth period of larva is about 14 days. 5. The period from the unifection to death is an indirect proportion to number of the eggs. 6. The period from the pupation to flying is about 14 days, depending upon the temperature.

• Korean Journal of Poultry Science
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• v.23 no.2
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• pp.77-84
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• 1996

The purpose of this paper is to introduce the present situation of broiler breeder industry, and to investigate some problems related to it in Korea. The number of broiler breeding farms were 231 in 1990. It peaked to 264 in 1992, but decreased afterward to 232 in 1995. The number of broiler parent stock were over 4 millions since 1992 except in 1993. The number of commercial chicks produced per breeding hen was around 100, which is far below to the suggested values of breeding companies. The number of hatching eggs produced per breeding hen were 168 eggs in US, 156~170 eggs in Thailand, and 160~170 eggs in China. Factors involved in the lowered performances of broiler parent stock in Korea appear to be 1) the poor isolation of breeding farms from commercial broiler farms, causing easy contamination with various diseases, 2) the failure to provide proper environment to the breeder, and 3) the failure to control body weight during laying periods.

• Journal of Aquaculture
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• v.9 no.4
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• pp.321-327
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• 1996

Production of resting egg from the Korean rotifer, Brachiunus plicatilis (L and S-type) was investigated at different temperatures (L-type : 20, 24, $28^{\circ}C$, S-type : 28 32, $36^{\circ}C$) and salinities (10, 20,30 ppt). The rotifer was cultured in 25 ml test tube and fed on Nannochloris oculata. With regard to mixis rate, L-type rotifer showed higher rate at lower temperature, and the highest rate was observed at 20 ppt of salinity at each temperature of the experiment. However, for S-type rotifer, the optimum temperature and salinity were $28\~32^{\circ}C$ and 20 ppt, respectively. The highest number of resting egg was 173 eggs/ml in 16 days at $24^{\circ}C$, 10 ppt for L-type rotifer and 410 eggs/ml in 14 days at $28^{\circ}C$, 10 ppt for S-type rotifer. The maximum number of resting egg produced per 10,000 rotifers was 8,122 eggs at $20^{\circ}C$, 20 ppt for L-type rotifer and 8,700 eggs at $28^{\circ}C$, 20 ppt for S-type rotifer. The maximum number of resting egg produced $10^8$ cells of N. oculata was 50.7 eggs for L-type rotifer ($24^{\circ}C$, 20 ppt) and 79.6 eggs for S-type rotifer ($32^{\circ}C$, 10 ppt). The number of resting egg produced per day was $1\~11$ eggs/ml for L-type rotifers and $21\~35$ eggs/ml for S-type rotifer in 9 combination experiments. In this study, S-type rotifer is better than L-type rotifer in resting egg production, and the optimum temperature and salinity for resting egg production were $20^{\circ}C$, 20 ppt for L-type rotifer and $28^{\circ}C$, 20 ppt for S-type rotifer. This result shows the difference of Korean rotifer in the optimum condition for resting egg production from other rotifers reported earlier.

• Korean Journal of Veterinary Service
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• v.25 no.2
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• pp.111-116
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• 2002

To demonstrate the prevalence of Toxocara spp eggs in public playgrounds in Seoul city, sand samples collected from March to November in 2001 were examined. Of 2,600 sand samples from 650 playgrounds surveyed, 41 sands from 39 places(6%) had Toxocara rims eggs. Sand samples in apartment complex were more contaminated(9.7%) with the eggs than in residential area(2.4%). Toxocara canis eggs in sands were found in large number of in the spring but other seasons were less found.