• Journal of Ecology and Environment
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• v.30 no.4
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• pp.287-292
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• 2007

We monitored a breeding population of the Asian toad (Bufo gargarizans), in the Wonheunge pond at Sannamdong, Chungju, from 5 March to 11 April, 2006 and 14 February to 31 March, 2007 to investigate their movement patterns, breeding population sizes, and physical characteristics. Terrestrial migration to the pond started on 5 March in 2006 and 14 February in 2007. We captured a total of 266 immigrating individuals (213 males, 53 females) in 2006 and 307 (222 males, 85 females) in 2007, and found 50 adults apparently killed by motor vehicles while migrating to the pond in 2007. Emigration from the pond to terrestrial sites started on 15 March 2006 and 5 March 2007. We captured a total of 245 emigrating toads (181 males, 65 females) in 2006 and 99 (92 males, 7 females) in 2007. An additional 10 emigrating adults were found dead on the road. During both the immigration and emigration periods, two peaks in capture frequency appeared for each sex in each breeding season. The immigration peaks corresponded with higher temperatures, while the emigration peaks corresponded with high humidity. Migrating Asian toads showed sexual size dimorphism and a male-biased sex ratio. Body weights and SVL (snout-vent length) of immigrating and emigrating individuals were negatively related with migration dates.

• Korean Journal of Veterinary Service
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• v.32 no.4
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• pp.369-375
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• 2009

This study was attempted to survey the prevalence of heartworm infection among 253 dogs (male 167, female 86) on the 16 breeding farms in southern Gyeongnam area in May to December 2007. The results obtained from this experiment were summarized as follows; Fifty seven (22.5%) of the 253 examined dogs were heartworms-antigen positive, while twenty five dogs were Microfilaria positive by the modified Knott's method. The regional infection rates were of 25% in Tongyeong and 21% in Goseong, and on the breeding environment aspects, infection rates were lower in rural area than urban area farms. The infection rates were higher in female (26/86, 30.2%) than male dog (31/167, 18.6%). The infection rates by breeding size of farms were 31% (11/35) at <20 head, 26%(35/135) at 20~50 head and 13% (11/82) at >50 head. The infection rates of heartworm in examined dogs at the age of <2, 2~4 and >5 were 10.7% (8/75), 26% (40/154) and 37.5% (9/24), respectively. In the microfillaria-infected 25 dogs, identified Dirofilaria immitis of 21 (84%) using PCR. The dogs infected with heartworm showed the increased number of eosinophil.

• Journal of Ecology and Environment
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• v.44 no.2
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• pp.106-114
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• 2020

Background: Determining patterns of habitat use is key to understanding of animal ecology. Approximately 1% of bird species use brood parasitism for their breeding strategy, in which they exploit other species' (hosts) parental care by laying eggs in their nests. Brood parasitism may complicate the habitat requirement of brood parasites because they need habitats that support both their host and their own conditions for breeding. Brood parasitism, through changes in reproductive roles of sex or individual, may further diversify habitat use patterns among individuals. However, patterns of habitat use in avian brood parasites have rarely been characterized. In this study, we categorized the habitat preference of a population of brood parasitic lesser cuckoos (Cuculus poliocephalus) breeding on Jeju Island, Korea. By using compositional analyses together with radio-tracking and land cover data, we determined patterns of habitat use and their sexual and diurnal differences. Results: We found that the lesser cuckoo had a relatively large home range and its overall habitat composition (the second-order selection) was similar to those of the study area; open areas such as the field and grassland habitats accounted for 80% of the home range. Nonetheless, their habitat, comprised of 2.54 different habitats per hectare, could be characterized as a mosaic. We also found sexual differences in habitat composition and selection in the core-use area of home ranges (third-order selection). In particular, the forest habitat was preferentially utilized by females, while underutilized by males. However, there was no diurnal change in the pattern of habitat use. Both sexes preferred field habitats at the second-order selection. At the third-order selection, males preferred field habitats followed by grasslands and females preferred grasslands followed by forest habitats. Conclusions: We suggest that the field and grassland habitats represent the two most important areas for the lesser cuckoo on Jeju Island. Nevertheless, this study shows that habitat preference may differ between sexes, likely due to differences in sex roles, sex-based energy demands, and potential sexual conflict.

• Journal of Ecology and Environment
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• v.31 no.1
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• pp.37-43
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• 2008

We analyzed soil characteristics, soil seed banks, and plant communities in a small islet in Ganwol Lake from May 2005 to August 2006 to examine the forces driving plant settlement on sand bars and the effects of plant settlement patterns on nesting sites of little terns (Sterna albifrons). The soil nutrients contents in a site where the feces of wintering birds accumulate (N: 15.4 mg/kg, P: 10.5 mg/kg, LOI: 0.51 %, pH: 6.8) and a site where organic sediments accumulate (N: 20.7 mg/kg, P: 16.4 mg/kg, LOI: 0.40%, pH: 6.6) were much higher those of a control site which was not affected by bird feces and organic sediments (N: 4.1 mg/kg, P: 5.4 mg/kg, LOI: 0.41%, pH: 6.7). However, a seed bank was formed only on the site with accumulated organic sediments. Plant settlement was accelerated by feces from wintering birds and organic sediment accumulation on sand bars in Ganwol Lake. The percentage of area disturbed by human activities increased from 0.2% in May 2005 to 13.9% in August 2006, and the percentage of annual communities increased from 27.5% to 43.3%, but the percentage of open area decreased from 55.2% to 28.0% from May 2005 to August 2006. These increases in disturbed area and annual communities decreased the open area for breeding of little terns. The enlargement of P. communis and T. angustata communities was suppressed by irregular flooding. These results provide useful information for the management of little tern breeding sites for conservation purposes.

• Journal of Environmental Science International
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• v.21 no.5
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• pp.647-654
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• 2012

The goal of this study was to investigate the distribution chart of management and satisfaction through Hanwoo education program and to provide fundamental data and development conformity available on the management and educational program to managers. In this study, we chose 75 managers taking part in Hanwoo education program as pre-test and applied satisfaction for education program to 33 managers randomly selected as post-test. The results of this study are as follows: First, age and academic career had a significant (P<0.05) effect on breeding size, breeding career, sales, and management methods. This may be due to the fact that managers in Hanwoo industry tended to raise academic standards and the age group moved towards young age rather than middle and old ages. However, an academic career was unaffected by sale and management methods. Second, managers who randomly selected the education program showed higher satisfaction about the program and lower or usual interest and intention in the educational environment, incidental facilities, and reviews. In conclusion, to equip the constituent parts of education program with entire propriety and an effective running system, information on breeding size and breeding career for managers in Hanwoo Industry with respect to age and academic career had to be clearly premeditated. It also needed the educational program to look at it from the standpoint of the managers.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.340-346
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• 2013

We have confirmed the first case of mass mortality which occurred in the wild populations of larval toad, Bufo bufo gargarizans during 2007~2009 at Mangwel pond, which is a long time breeding site, and is located at the south eastern area in Daegu. We have investigated through microbiological tests the cause of mass decease of the larval toad, and detected numerous bacteria from the intestine by histological examines and cultures. The pathogen isolated from the infected larval toads has been identified as Aeromonas hydrophila, which is widely distributed in aquatic environment. However, this phenomenon of mass lethal pattern of the larval toad disappeared at the breeding pond after maintaining better water levels and low temperature in spring during breeding season in 2010. We propose that the high temperatures during the 2007~2009 breeding season resulted in lower water levels and drier conditions leading to explosive propagation of A. hydrophila in the pond which impacted the larval toad's immune function.

• Korean Journal of Breeding Science
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• v.42 no.3
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• pp.245-247
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• 2010

A new pasqueflower (Pulsatilla koreana) variety, 'Gyeobi,' was derived from a mutation of native P. koreana at the Jeollanamdo Agricultural Research and Extension Services (JARES) in Naju, Korea. The 'Gyoebi' was obtained by treating seeds with 3 mM of a chemical mutagen, sodium azide, for 16 hr in 2001. The variety was established in 2005 after two years of selective breeding. 'Gyeobi' is characterized by reddish purple flowers with 12 double petals. The inherent characteristics of the variety are deep yellow anthers and reddish purple stigmas. The agronomic characteristics of the variety are 6.3 flowers per plant, 26.4 cm in flower height, 14.2 cm in leaf length, 7.5 cm in flower width, and 11.0 cm in bract width.

• Animal Bioscience
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• v.36 no.7
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• pp.1067-1074
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• 2023

Objective: Better feed efficiency can be achieved by selecting rabbit genotypes with lower residual feed intake (RFI) under high ambient temperatures. Methods: Two genotypes of rabbits (Jabali, Saudi local breed and imported, Spanish V-line) were used to derive RFI and to investigate the relationship between RFI and productive traits. In total, 250 animals (125 each) were housed in individual wire mesh cages in a semi-closed rabbitry. Growth performance, feed criteria, carcass evaluation, biochemical blood analysis, and immune responses were determined. Results: Superiority in growth performance, feed efficiency, carcass characteristics, and cellular immunity was recorded in the Jabali breed compared to the V-line genotype. According to regression analysis, a significant effect of daily body weight gain was found, upon computing the expected feed intake in both genotypes. Moreover, mid-body weight^0.75 had a significant effect only in the Jabali breed. Positive correlation coefficients between RFI and dry matter feed intake or feed conversion ratio were found. The same trend in this relationship between RFI and productive traits was observed in some cases for both genotypes. An opposite trend in correlations was observed in the studied genotypes for some traits. Conclusion: The results suggest that the relationship between RFI and productive traits must be taken into consideration in rabbit breeding programs under the prevailing environment. However, further studies are required to investigate the effect of rabbit genotype and environmental factors on computing RFI.

• KIEAE Journal
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• v.5 no.2
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• pp.27-34
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• 2005

The purpose of this study were to examine actual conditions of apartment residents living with their companion animals and to identify their residential stress and needs of planning elements under those conditions. Questionnaire survey was adopted in this study, and 100 cases were used for data analysis. The subjects for this study were limited to the residents breeding pets in their apartments. The results of this study are as follows: Most of the residents share their living spaces with pets together like their family without spatial restrictions. They indicated problems related to breeding pets in their residence such as walking the dog, cleaning home, leaving pets alone, noise and unpleasant smell. However, they didn't seem to be stressed a lot for their living environments. In terms of residential planning elements, floor plans for effective natural ventilation, balcony with sufficient sunlight, sound proof system, easy-maintenance interior material, unlash area, rubbish bin, mechanical ventilation and central vacuum system and safe electric outlet were highly indicated.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.3
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• pp.413-422
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• 2000

In the class of models which include random effects, the variance component estimates are important to obtain accurate predictors and estimators. Variance component estimation is straightforward for balanced data but not for unbalanced data. Since orthogonality among factors is absent in unbalanced data, various methods for variance component estimation are available. REML estimation is the most widely used method in animal breeding because of its attractive statistical properties. Recently, Bayesian approach became feasible through Markov Chain Monte Carlo methods with increasingly powerful computers. Furthermore, advances in variance component estimation with complicated models such as generalized linear mixed models enabled animal breeders to analyze non-normal data.