• Korean journal of applied entomology
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• v.60 no.4
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• pp.449-462
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• 2021

We analyzed the effects of temperature on the survival, development, and reproduction of the non-diapause Asian corn borer, Ostrinia furnacalis (Lepidoptera: Crambidae). A 16:8 h light:dark photoperiod was supplied to the non-diapause stages of O. furnacalis. The insects were raised on an artificial diet at seven constant temperatures between 15 and 35℃ for immature stages, and eight temperatures between 13 and 33℃ for the adult stage. The survival rate of eggs exceeded 70% at all temperatures, whereas survival of larvae was as low as 7.4% at 15℃. The developmental periods of the immature stages decreased with increasing temperature, but the larval period did not decrease further at 35℃. The pupal weight increased with increasing temperature, but the female weight decreased at 35℃. Variations with different last larval instars within the colonies at different temperatures were observed. Adults produced offspring at all tested temperatures. Adult longevity and the pre-oviposition and oviposition periods decreased with increasing temperature, but the pre-oviposition period increased at 33℃. Total fecundity exceeded 400 viable eggs at 22℃ and 31℃. The mean daily fecundity during the oviposition period and the mean daily fecundity on the day of oviposition increased with increasing temperature, but decreased at 33℃. Daily fecundity sharply increased at earlier adult ages and slowly decreased thereafter. The simulated oviposition frequency was greatest at 22℃. The lower developmental threshold temperatures were estimated to be the lowest at 9.7℃ for the first instar larva and the highest at 14.7℃ for the 5th to last instar larval stage, using a linear model.

• Korean journal of applied entomology
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• v.43 no.2
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• pp.135-141
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• 2004

This study was carried out to review the distributional data of Dorcus hopei in Korea and to investigate ecological characteristics to develop a mass rearing technique of the species. The coupling period of the male and female was needed at least 2 weeks in condition of 6 months after emergence, and the optimal sex ratio for oviposition was 2♀：1♂. Eggs were laid singly, up to 27.3 per female. The pre-ovipostion period was average 147.3 days, egg-period was 15.6 days on the average, and oviposition period was at least 120 days. The optimum size of oviposition room was 55${\times}$40${\times}$35 cm with 3-4 oviposition-trees cut in size of 15${\times}$15 cm. Quercus acutissima was highly preferred for the oviposition. Developing period of each instar in the insectary (25$^{\circ}C$, 75％ R.H.. 16L：8D) was 24.1 days for the 1st instar,29.8 days for the 2nd, and 131.2 days for the 3rd instar, and 28.9 days for the pupa. The longevity of adults was longer than 35 months. The period of induced dormancy was needed at least 3-4 months.

• Journal of Aquaculture
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• v.10 no.4
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• pp.463-472
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• 1997

Floating and hatching rates, size and survival activity index(SAI) of spawned eggs of red spotted grouper, Epinephelus akaara were studied to understand egg qualities during the spawning periods in 1992, 1993 and 1995. The fish spawned from mid-July to mid-August when temperature ranged 23~$28^\circC$. Floating, fertilization and hatching rates were higher in the eggs from early to middle than those from late during the spawning period. SAI ranged 1.8~9.6, and it was closely related to survival rate until mouth operning time (SMOT). Egg diameter decreased gradually with the time of spawning, while diameter of oil globule was constant during the spawning periods. Induced spawnings were carried out with one injection of HCG over 5, 000 IU/kg body weight. Floating, fertilization and hatching rates of the induced spawning eggs were higher than those of untreated ones. Thus, induced spawning method with HCG was recommended for collecting fertilized eggs in bulk. Optimal time for the collection of high quality eggs was supposed to be from early to middle during the spawning periods. Considering that egg qualities were vulnerable within the period, hatchability, incidence of malformed larvae, SMOT and SAI were factors to be considered together to get good quality of eggs.

• Korean Journal of Ichthyology
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• v.25 no.2
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• pp.74-81
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• 2013

Factors influencing spawning or respawning conditions of the bitterling, Acheilognathus signifer were investigated in the aquariums. Inducing the female spawning was more sensitive to the mussel than the male. The ovipositor of the female was periodically elongated and reduced from 4 to 6 days with the presence of mussel. During of the elongated state of the ovipositor was 1 to 2 days. As the result of natural spawning in the aquariums, it takes 1 to 3 days (mean 1.6) to spawn. The most important factor to respawn spawned females again was the mussel. It takes 11 to 53 days (mean 29.5) from extraction to reextraction of females which have elongated ovipositor. The egg numbers of reextraction were 2 to 41 (mean 19). This experiments showed the tendency the more standard length of females grows, the more the number of extracted eggs increases.

• Journal of Aquaculture
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• v.4 no.2
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• pp.85-95
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• 1991

Spawning inducement of flounder, Paralichthys olivaceus, was attemped by the control of water temperature and photoperiod from June 1, 1989 through January 5, 1990 (189 days) Water temperature was gradually decreased from $21.7^{\circ}C$ to $10.6^{\circ}C$ which was the minim biological temperature for spawning of flounder. Water temperature was increased asain to $15^{\circ}C$ gradually, and then maintained at this level through the end of spawning. Photoperiod was also changed gradually from 10L/14D in June 1, 1989 to 14L/10D in July 25, 1989. Spawning of the fish occurred from October 4, 1989 through January 5, 1990 (93 days). The average number of eggs spawned during the spawning season per female were 2.67 billion. The first spawning occurred on the 60th day after the time of minimun water temperature $10.6^{\circ}C$. The water temperature and photoperiod at the first spawning were $13^{\circ}C$ and 14L/10D respectively It took 71 days to spawn since the photoperiod had changed from 10L/14D to 14L/10D. Spawning period can be devided into three terms. The first term was continued for 30 days from the beginning of the spawning. The second term for 41 days was the major spawning period followed by the third term, the final period of the spawning, for 22 days. The percentage of average fertilization rate of the eggs in the first, second and third spawning terms were $37.4{\%},\;54.1\%\;and\;19.6\%$, respectively. Feeding rate was increased in the maturing period but, decreased in the spawing period. During the final spawning period, the abrubt decreasing of the feeding occurred again.

• Korean Journal of Poultry Science
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• v.17 no.4
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• pp.318-326
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• 1990

This experiment was conducted to determine the economic housing density levels on caged laying hens The experiment was carried out with 600 ISA Babcock strain of white coder and 450 ISA Brown strain of brown color for production period(21－72 weeks) from May 11. 1987 to June 27. 1988. The levels of housing density was employed 5 or 6 by hen's color from 272 to 920$\textrm{cm}^2$/per hen. The results obtained were summarzed as follows ： 1. Although there were not statistically significant among the housing density levels, The body weight gain for pullet period(14－20 weeks) were in case of white pullet the lowest at the group of high crowding density (272$\textrm{cm}^2$/per pullet) and in case of Brown pullet was the lowest at the group of high crowding density(306$\textrm{cm}^2$/per pullet). 2. Viabillity of pullet from 14 to 20 weeks were more 97% and there urere not statistically significant among the housing density. 3. Viabillity of laying hens was increased as increasing housing density through the etire product period(21－72 weeks) but 453$\textrm{cm}^2$/per hen group(in case of brown hen) showed a significant difference (P＜.05). 4. Rate of egg production through the etire production period(21－72 weeks) were significantly increased by increasing housing density (P＜.05 or .01). 5. Average egg weight through the entire production period(21－72 weeks) was not significantly different among housing density levels at all laying kent 6. In case of white strain, egg mass per hen among treatment during the age of 63－72 weeks were decreased by increasing housing density, meanwhile, in case of brown strain were increased by decreasing housing density during the whole period and there were significant different among the all treatment 7. There were no significant different in feed intake among the all treatment through the entire production period(21－72 weeks) at the white strain laying hens but in case of brown strains, Feed intake were increased by increasing housing density and feeding spece/per hen, and there were significant different among the all treatment 8. Feed requirements per egg at white strain was the highest when the 272$\textrm{cm}^2$/per hen levels and at the brown strains was the highest when the 306$\textrm{cm}^2$/per hen levels, however, among the other treatment were no significant.

• KOREAN POULTRY JOURNAL
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• v.40 no.10
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• pp.124-127
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• 2008

국내 산란계 시장은 짧은 기간동안 부단한 노력 끝에 현재 5,600만수(1,830여 농가) 규모로 급속도로 발전해왔다. 평균 3만수 농가로, 그 중 10만수 이상의 대군농가는 100여 농가, 20만수 이상 사육농가는 30여 농가로 국내 산란계산업 발전을 위해 선두적인 역할을 하고 있다. 이번 호에는 30년간 산란계 전문 사육으로 현재 30여만수 이상의 규모로 자리매김한 무지개농장 한기석 사장을 만나 보았다.

• 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.9 no.1
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• pp.35-42
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• 1982

Data pertaining to the first generation of a Synthetic White Leghorn flock were used to estimate the heritabilities of and genetic correlation between partial egg production(egg number or percentage) or diversely segmented part records and other traits such as age at sexual maturity, residual and annual egg production, and to compare the expected genetic gain from selection on partial egg number or partial percent production with correlated response in other traits. The estimated heritabilites for six measures of egg Production were ranged from 29 to 35, while heritability for age at sexual maturity (SM) was intermediate (48). Genetic correlations between partial egg number (P) and annual egg number. (A), and partial percent production (P') and annual percent production (A') were 51 and 72, respectively. Genetic correlation between P and SM was estimated largely negative (-.64), while correlation bettween P' and SM was positively intermediate(34). In comparing direct response from selection on partial production (P or P') with another response in correlated trait, selection on P would be 25% more efficient than selection of P' for improving A, while selection of P' would be 94% more efficient than selection P for improving A' For shortening SM selection of P would be 98% more efficient than selection on P'.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.173-179
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• 2013

This study was investigation for primary bionomical characteristics, emergence rate of wintering type pupa and oviposition preference, of Papilio xuthus. The emergence rate of wintering type pupa stored at cold chamber($4{\pm}1^{\circ}C$) was 85%, after 10 months. The average emergence rate of wintering type pupa during storage was 89.6%, and the emergence periods were $7.9{\pm}1.9days$ in room temperature. Mating ratio in large oviposition room, $6,000{\times}6,000{\times}3,500$ mm($W{\times}L{\times}H$), was $86.7{\pm}5.8%$ higher than $63.3{\pm}15.3%$ in small room, $2,500{\times}3,000{\times}2,000$ mm($W{\times}L{\times}H$). But the number of eggs in the large room were $137.0{\pm}16.5$ fewer than $141.7{\pm}20.4$ in the small room. As a result of oviposition preference experiment on three different host plants, 10 mated female laid $141.7{\pm}27.8$ on the leaves of Phellodendron amurensew more than $67.7{\pm}20.6$ on Zanthoxylum schinifolium and $77.0{\pm}21.8$ on Citrus unshiu. The egg periods were $4.4{\pm}0.8$ days after oviposition, and the hatchability was 92.2% in $25^{\circ}C$ room condition. The larval period were $19.9{\pm}2.1$ days in the high temperature, long day condition($25^{\circ}C$, 14L : 10D). The headwidth of each developmental larval stage were $0.72{\pm}0.02$(1st), $1.19{\pm}0.02$(2nd), $1.65{\pm}0.05$(3rd), $2.43{\pm}0.07$(4th), $3.21{\pm}0.12$(5th). The pupal ratio was 91.6%. The pupal period were $8.8{\pm}0.9$ days, and the emergence rate was 92.2%.