• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.90-90
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• 2022

Nicaragua is located in Central America, climatic conditions are considered tropical dry forest. Statistics reflex that in Nicaragua exits 24,000 rice farmers. National rice production only covers 73% of the national consumption. It exists two sowing system: irrigation and rainfed. Varieties used in both systems are mid-late maturity (120-135 days), there are 14 released varieties for irrigation, eight for rainfed, and eight landraces used in rainfed. The current breeding system (introduction of lines from Colombia) has increased the national production, however, has some limitation due to the lack of enough variability, reducing the proability of finding good genotypes and therefore the possibility of satisfying 100% of the demand. The purpose of this study was to analyze the problems that must be resolved in the short and long term to improve rice productivity in Nicaragua. In this paper we explain some proposal for an improvement plan. The selection of varieties with high adaptability to various cultivation environmental conditions it is necessary, also to thoroughly manage seed purity to supply certified seeds. In rice cultivation technology, it needs to improve seedling standing and weeding effect by improving soil leveling and water-saving cultivation technology. Also, proper fertilization and planting density must be established in irrigated and rain-fed areas. Furthermore, capacity must be strengthened by collecting and training with the most recent agricultural technology information, as well as by revitalizing the union rather than the individual farmer. It is necessary to develop varieties highly adaptable to the Nicaraguan cultivation environment, as well as to expand irrigation facilities and cultivation technology suitable for weather conditions in rain-fed areas. Last, it is necessary to maintain the consistency of agricultural policy for continuous and stable rice production in response to climate change events such as drought or intermittent heavy rain.

• Asian-Australasian Journal of Animal Sciences
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• 제12권6호
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• pp.846-849
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• 1999

Angus postweaning daily gain (PWDG) were analyzed to investigate heterogeneous variance by sex. A set of data (16,239 records) was divided into six sub-data sets according to level of environment. REML estimation was conducted by a multitrait model, where PWDG in each sex was treated as a separate trait. Estimates showed diversity among environmental levels, where the heritability for heifers was high in good environment but low in poor environment. The bull's estimates varied among environmental levels. The largest heterogeneity of phenotypic variance between sexes was estimated in a data set of the poor environment level. The genetic correlations between the heifer's PWDG and the bull's PWDG were high in the good environment and low in the poor environment (-0.17). The results suggest existence of genotype by sex interaction in the poor environment.

• 한국환경생태학회지
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• 제22권2호
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• pp.152-158
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• 2008

이 연구는 2003년부터 2006년까지 4년간 대구시 수성구 팔현리 백로류 집단번식지 인근의 도로공사가 백로류 번식에 미치는 영향을 분석하였다. 2003년부터 2005년까지 3년간 공사가 진행되면서 백로류 개체수는 감소하였다. 공사가 중단된 2006년에는 황로를 제외한 왜가리와 중대백로의 개체수가 증가하였고, 왜가리는 다른 백로류에 비해 공사의 영향을 가장 많이 받은 것으로 나타났다. 중대백로, 쇠백로 및 해오라기의 개체수도 공사기간동안 감소하였다. 둥지목의 벌목과 번식지의 일부가 절개된 후 백로류의 둥지는 도로변에서 번식지의 안쪽으로 이동하는 경향이 나타났다. 조사기간 동안 번식지내 백로류의 분변으로 인한 고사목의 증가와 태풍으로 인한 도복으로 둥지목의 그루 수는 감소하였고, 둥지목 당 번식 둥지의 수는 늘어났다. 둥지목의 구성비율은 매년 소나무의 비율이 낮아지고, 아카시와 참나무의 비율이 증가하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권11호
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• pp.1623-1627
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• 2005

Heavy metal pollution has become a serious health concern in recent years. Dogs are a very good indicator of the pollution load on the environment. They share people's environment and are exposed to the action of the same pollutants. This study estimated the heavy metal contents in the serum of dogs in domestic districts, and assessed the age, sex, feeding habits, living area, breeding environment and smoking habit of the owners. The findings suggest that dogs can be used to monitor the environmental quality of heavy metals. The mean concentrations of heavy metals in the dog serum from 204 samples (108 male and 96 female) were 0.22${\pm}$0.01 $\mu$g/ml, 0.24${\pm}$0.04 $\mu$g/ml, 0.61${\pm}$0.08 $\mu$g/ml, and 0.50${\pm}$0.06 $\mu$g/ml (for Cd, Hg, Pb, and Cr), respectively. Concentrations of Pb, Cd, Hg, and Cr in the dog serum were higher in Yeongnam including Ulsan, and Seoul higher than those of Chungchong and Honam, especially Pb concentration, which was significantly higher (p<0.01). Concentrations of Cd, Hg, Pb, and Cr in serum, were increased by age (p<0.05). When commercial pet food was provided to dogs, Cd and Cr concentrations were significantly higher in dog serum than dogs fed a human diet (p<0.01 in Cd and p<0.05 in Cr). Heavy metal concentrations of dogs owned by smoking owners, were higher than non-smoking owners although there was no significant difference.

• Asian-Australasian Journal of Animal Sciences
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• 제18권8호
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• pp.1135-1140
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• 2005

Dogs are a very good indicator of the pollution load on the environment. They share people's environment and are exposed to the action of the same pollutants. This study was to estimate the heavy metal contents in dog hairs in domestic districts, and to assess effects of age, sex, feed habits, living area, breeding environment and smoking habit of owner. The mean concentrations of heavy metals in 204 samples were 0.09${\pm}$0.10 ${\mu}g$/g, 0.21${\pm}$0.09 ${\mu}g$/g, 0.82${\pm}$0.09 ${\mu}g$/g and 0.48${\pm}$0.07 ${\mu}g$/g (Cadmium (Cd), Mercury (Hg), Lead (Pb) and Chromium (Cr)) in dog hairs, respectively. Concentrations of Pb, Cd, Hg and Cr in dog hairs in Yeongnam including Ulsan and Seoul, were higher than in Chungchong and Honam, and concentrations of Pb were significantly different (p<0.01). Concentrations of Cd, Hg, Pb and Cr in dog hairs increased with age (p<0.05). Only dogs fed commercial pet foods had significantly higher Cd and Cr concentrations in hairs than dogs fed dog feed and human diet (p<0.01 in Cd and p<0.05 in Cr). Cr concentrations of dog hairsfrom dogs kept on cement floors were the highest of the other environments (p<0.01). Heavy metal concentrations of dogs owned by smokers, were higher than dogs of non-smokers, but there were no significant differences.

• 한국생물환경조절학회:학술대회논문집
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• 한국생물환경조절학회 1996년도 국제심포지움 21세기 첨단식물생산시스템의 실용화
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• pp.41-62
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• 1996

Since 1966 tissue culture has been used as a tool for the production of disease indexed stocks from selected plants and their rapid (clonal) mass propagation through the procedure now referred to as micropropagation. The major advantages have been the rapid introduction of new plant cultivars, created within conventional and mutation breeding programmes, as healthy stock for beneficial distribution and the expansion of the world wide horticultural industry. (omitted)

• 한국환경생태학회:학술대회논문집
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• 한국환경생태학회 2005년도 임시총회 및 학술논문발표회
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• pp.154-156
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• 2005

• 한국양식학회:학술대회논문집
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• 한국양식학회 2006년도 수산관련학회 공동학술대회 발표요지집
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• pp.235-236
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• 2006

• Asian-Australasian Journal of Animal Sciences
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• 제28권8호
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• pp.1090-1094
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• 2015

The aim of the study was to select traits that may constitute a prospective criterion for breeding value prediction of young horses. The results of 1,232 starts of 894 four-, five-, six-, and seven-year-old horses, obtained during jumping championships for young horses which had not been evaluated in, alternative to championships, training centres were analyed. Nine traits were chosen of those recorded: ranking in the championship, elimination (y/n), conformation, rating of style on day one, two, and three, and penalty points on day one, two, and three of a championship. (Co)variance components were estimated via the Gibbs sampling procedure and adequate (co)variance component ratios were calculated. Statistical classifications were trait dependent but all fitted random additive genetic and permanent environment effects. It was found that such characteristics as penalty points and jumping style are potential indicators of jumping ability, and the genetic variability of the traits was within the range of 14% to 27%. Given the low genetic correlations between the conformation and other results achieved on the parkour, the relevance of assessment of conformation in four-years-old horses has been questioned.

• Journal of Ecology and Environment
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• 제31권1호
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• pp.9-15
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• 2008

Growth and reproduction of Palaemon serrifer were described and analyzed in a population inhabiting tide pools in warm temperate waters in Korea. The water temperature varied greatly in the tide pools, ranging from 8$^{\circ}C$ to 27.8$^{\circ}C$ Population structure and growth were investigated using size frequency distribution data collected from January to December 2003. Sex ratios fluctuated, but were almost equal during the breeding period. Growth was continuous and size increased gradually throughout the year. Adult females were larger and grew faster than males. von Bertalanffy growth parameters for a one-year sample of females and males were estimated as $L_{i\ddot{A}}$ = 11.32, K = 0.311, $t_0$ = -0.4115 and $L_{i\ddot{A}}$ = 8.36, K = 0.228, $t_0$ = -0.9693 respectively. Breeding was seasonal, starting in May, peaking in August, and finishing by the end of August. The species showed continuous production of successive broods. Laboratory observation showed that females with embryos near hatching had ovaries filled with vitellogenic oocytes ready for spawning. The reproductive output (effort) of each female (mean number of eggs: $552{\sim}1355$) was not high. The mean embryo volume, $0.078mm^3$, is relatively small, indicative of low energy allocation to each embryo. Recruitment of juveniles was closely linked to the breeding period, beginning in September.