• Korean Journal of Poultry Science
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• v.31 no.4
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• pp.299-306
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• 2004

The objective of this study was to investigate the influence of egg storage, broiler breeder age, and the change of egg weight during incubation on growth rate of chicks and 43-day-old dressing percentage. The trials involved hatching eggs obtained from 27-wk-old hens and stored for 6 d for the Young-EXP group, from 28-wk-old hens and stored for 0 d for the Young-CON group, from 51-wk-old hens and stored for 6 d for the Old-EXP group, and from 52-wk-old hens and stored for 0 d for the Old-CON group, The hens were two commercial broiler breeder flocks of the same strain (Cobb) but of different egg producing stages(early and middle stages of egg production). The chicks were grown on floor pens for 6 wks, The differences of setting egg weights between Old-CON and Old-EXP groups were 1 g, but those between Young-CON and Young-EXP groups were 2.9 g(P<0,05). The loss of egg weight during 18 d incubation did not greatly differ among four groups, but the loss of egg weight during 21 d incubation was significantly (P<0.05) more in the middle stage of egg production groups than in the early stage of egg production groups. The mean birth weights of the middle stage of egg production groups were significantly(P<0,05) heavier by 8,7 g than those of the early stage of egg production groups; however, the differences of 6-wk-old body weight were not significant between egg producing stages. The differences of body weights in both egg producing stages were not significantly influenced by egg storage period in overall wks of ages. Egg storage and hen age did not greatly influence to the 43 d dressing percentages, either, The correlations of the setting egg weight with 18 d egg weight during incubation, growth rate of chicks, or 43 d dressing percentage were not significant.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2004.11a
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• pp.111-112
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• 2004

참옻나무 추출액이 산란계의 생산성과 계란품질, 장내미생물 변화 및 영양소 소화율에 미치는 영향을 구명하고자 산란졔 Isa brown 57주령 480수를 공시하여 8주간 케이지에서 사양시험을 실시하였다. 산란율, 산란량 및 사료요구율은 참옻나무 추출액 5000 ppm 급여구가 산란율이 무첨가 대비 유의적으로 향상되었으며, 전반적으로 추출물 급여구의 산란율이 증가하였다. 평균난중과 사료섭취량은 처리간 차이가 없었다. 난각강도, 난각후도는 추출액 급여구가 무첨가 대비 유의적으로 개선되었으며, 난황색 및 Haugh unit은 전 기간에서 추출액 첨가구가 개선되는 경향을 보였다. 맹장내 유산균과 E. coli는 처리간 차이를 보이지 않았으며, Salmonella는 무첨가 대비 추출액 급여구가 약간 낮은 경향을 보였으나 통계적 유의성은 인정되지 않았다. 영양소 소화율은 옻나무 추출액 급여구가 무첨가 대비 전반적으로 향상되는 결과를 보였다.

• KOREAN POULTRY JOURNAL
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• s.132
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• pp.45-48
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• 1980

산란계는 육계와는 달리 자본회전이 6개월이상 되므로 그동안 투자기간이 길기 때문에 자금계획을 철저히 세워 두어야 한다. 또한 사양기록표를 필히 준비하여 매일 작성하여 그 계군의 상황을 바로 알 수 있도록 철저한 기록을 하여야 한다. 그러므로서 사양관리의 지표가 되며 충분한 참고자료가 된다. 그리고 한 계군이 도태(경제적 수명) 될 때까지는 18개월 이상의 기간이 소요되므로 연중 방역계획을 수립하여 수시로 점검하는 자세가 필요하며 생산물인 계란을 연중 쉽게 판매할 수 있도록 시장유통 관계를 체계화하여 안정된 채란업을 할 수 있도록 하여야 한다.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.127-134
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• 2012

Microwave remote sensing can help monitor the land surface water cycle, crop growth and soil moisture. A ground-based polarimetric scatterometer has an advantage for continuous crop using multi-polarization and multi-frequencies and various incident angles have been used extensively in a frequency range expanding from L-band to Ka-band. In this study, we analyzed the relationships between L-, C- and X-band signatures and soil moisture content over the whole soybean growth period. Polarimetric backscatter data at L-, C- and X-bands were acquired every 10 minutes. L-band backscattering coefficients were higher than those observed using C- or X-band over the period. Backscattering coefficients for all frequencies and polarizations increased until Day Of Year (DOY) 271 and then decreased until harvesting stage (DOY 294). Time serious of soil moisture content was not a corresponding with backscattering over the whole growth stage, although it increased relatively until early August (R2, DOY 224). We conducted the relationship between the backscattering coefficients of each band and soil moisture content. Backscattering coefficients for all frequencies were not correlated with soil moisture content when considered over the entire stage ($r{\leq}0.50$). However, we found that L-band HH polarization was correlated with soil moisture content (r=0.90) when Leaf Area Index (LAI)<2. Retrieval equations were developed for estimating soil moisture content using L-band HH polarization. Relation between L-HH and soil moisture shows exponential pattern and highly related with soil moisture content ($R^2=0.92$). Results from this study show that backscattering coefficients of radar scatterometer appear effective to estimate soil moisture content.

• Korean journal of applied entomology
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• v.19 no.2 s.43
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• pp.85-89
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• 1980

This experiment was carried out to investigate the life history of the Three spotted plusia (Chrysodeixis agnata Staudinger) in the laboratory in 1976. (1) Female deposited $1202{\pm}150.6$ eggs during the oviposition period which was $13.3{\pm}1.2$ days. (2) Especially, larvae were distinguished with 5-instar type and 6-instar type. The egg period was 2 days and adult longevity was $21.29{\pm}3.15$ days for female and $19.14{\pm}2.47$ days for male. Larval period and pupal period were $15.36{\pm}1.59,\;7.82{\pm}1.01$ days for the 5-instar type and $16.92{\pm}1.08,\;8.23{\pm}1.09$ days for the 6-instar type. (3) Width of head capsule of the 5-instar type was $2.77\~2189mm$ and this of the 6-instar type was $2.78\~22.38mm$. (4) A highly significant correlation was recognized between the log-width of head capsule and the number of instar.

• KOREAN POULTRY JOURNAL
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• s.131
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• pp.91-97
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• 1980

• KOREAN POULTRY JOURNAL
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• v.24 no.4 s.270
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• pp.39-41
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• 1992

• KOREAN POULTRY JOURNAL
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• v.18 no.1 s.195
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• pp.154-159
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• 1986

• Korean Journal of Poultry Science
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• v.39 no.3
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• pp.215-222
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• 2012

This study was conducted to investigate the effects of supplementation diets of powdered mulberry leaves on egg production, egg quality and blood characteristics in laying hens. Laying hens were fed diets for 30 days containing 0% powdered mulberry leaves (Control), 1% powdered mulberry leaves (T1), 2% powdered mulberry leaves (T2), and 5% powdered mulberry leaves (T3). The egg production, yolk weight and albumen weight were no significant difference among treatment groups. The albumen weight was significantly decreased by the supplementation of powdered mulberry leaves in all treatment groups (P<0.05). The albumen high, yolk color score, egg sell thickness and egg shell breaking strength were no significant difference. The total cholesterol and triglyceride concentration of control was higher than T3, and the high density lipoprotein (HDL)-cholesterol concentration and glucose of control were lower than treatment groups (P<0.05). The white blood cell (WBC) was significantly increased by the supplementation of powdered mulberry leaves compared to the control (P<0.05). In conclusion, these data indicate that 5% powdered mulberry leaves supplementation was most effective in decreasing total cholesterol and triglyceride and increasing HDL-cholesterol, glucose and WBC.

• Korean journal of applied entomology
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• v.61 no.4
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• pp.563-575
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• 2022

Maruca vitrata is one of important pests in leguminous crops, especially red bean. We investigated the effects of temperature on development of each life stage, adult longevity and fecundity of M. vitrata for understanding the biological characteristics of the insect species at eight constant temperatures of 13, 16, 19, 22, 25, 28, 31, and 34℃. Eggs hatched successfully at all temperature subjected and larvae successfully developed to the adult stage from 16℃ to 31℃. The developmental period of egg decreased up to 31℃ and after then increased. The developmental period of larva and pupa, and adult longevity of M. vitrata decreased with increasing temperature. Lower and higher threshold temperature (TL and TH) were calculated by the Lobry-Rosso-Flandrois (LRF) and Sharpe-Schoolfield-Ikemoto (SSI) models. The lower developmental threshold (LDT) and thermal constant (K) from egg hatching to adult emergence of M. vitrata were estimated by linear regression as 12.8℃ and 280.8DD, respectively. TL and TH from egg hatching to adult emergence using SSI model were 14.2℃ and 31.9℃. Thermal windows, i.e., the range in temperature between the minimum and maximum rate of development, of M. vitrata was 17.7℃. In addition, we constructed the oviposition models of adult, using the investigated adult traits including survival, longevity, oviposition period and fecundity. Temperature-dependent development models and adult oviposition models will be helpful to understand the population dynamics of M vitrata and to establish the strategy of integrated pest management in legume crops.