• Horticultural Science & Technology
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• v.19 no.1
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• pp.60-65
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• 2001

'Shinil' pear cultivar (Pyrus pyrifolia Nakai) which was originated in a cross between 'Shinko' (non-patented, released in 1941) and 'Hosui' (non-patented, released in 1972) in 1978 was released as a middle season harvest variety. Its usual picking time coincided with 'Chuseok' season which is one of the most famous national holiday in Korea. The fruit showed high soluble solids content and good appearance. The cultivar was preliminarily selected in 1991, and its regional adaptability was evaluated in the name of 'Wonkyo Na-13' at 9 sites for four years from 1992, and finally selected and named in 1995. 'Shinil' is medium in tree vigor like 'Hosui' and spreading in tree habit as 'Niitaka', a leading cultivar in Korea, and consistently very productive. It has high resistance to black rot caused by Alternaria kikuchiana and pear necrotic spot caused by pear necrotic spot virus. Its full bloom is one day earlier than that of 'Niitaka' cultivar and harvest time is September 25 at Suwon area which is 3 days later than that of 'Hosui'. Fruit is round in shape with a deep medium stalk cavity and medium calyx basin and has attractive light yellow brown skin color. The fruit weight ranges between 300 and 400 g, which is similar to 'Chojuro', 'Shinko', and 'Hosui'. Soluble solid content is approximately at the level of 13-14 Brix, which is higher than that of 'Chojuro'. The flesh is cream-white, very juicy, and light grit with soft and fine texture.

• Korean Journal of Environment and Ecology
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• v.22 no.3
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• pp.332-337
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• 2008

This study was conducted to clarify the differences in bird communities in breeding season between coniferous forests of Mt. Namsan and Gwangneung areas from April to August 2006. We chose a study site of 10ha in size for territory mapping of breeding bird community in each area. There were significant difference in DBH distribution of trees and average foliage profiles between both study areas. Number of breeding species and pairs, breeding density, and bird species diversity were higher in Gwangneung area than in Mt. Namsan area. Number of bird species and breeding pairs belonged to hole and canopy guild were different between both study areas. The difference in breeding bird communities between both study areas may be related with forest structure. For the protection and management of birds, greater structural complexity would be needed in Mt. Namsan area.

• The Korean Journal of Ecology
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• v.25 no.5
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• pp.275-282
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• 2002

Preference of food plants of wild birds was shown in the order of Pinus densiflora, Celtis sinensis, Celastrus orbiculatus, Rosa multiflora, Taxus cuspidata, and Euonymus japonica, etc. The wild birds preferred the animal food(92.2%) rather than the vegetable food(32.7%) in breeding season(May through June), but preferred both animal and vegetable foods in non-breeding season(November through December). The rates utilzing artficial nest were 77.5%, 50.3%, 44.1% and 42.2% in Nosan, Sanho, Chinju-castle and Bibong parks, respectively. The wild birds used more the 3cm hole than 5cm hole.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.1
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• pp.57-61
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• 2003

A new silkworm variety, Chugangjam, with a sex-limited larval marking and high silk yielding for summer-autumn rearing season is $F_1$ hybrid between Jam 147, a Japanese race bred from P8503/8453, and Jam 148, a Chinese race from M8306/Jam 130. Jam 147, Japanese parent of the Chugangjam showed a high GCA (general combining ability) in pupation percentage and Jam 148, Chinese parent, showed a high GCA in pupation percentage and single cocoon weight. In the local adaptability test performed at 8 local areas in autumn of 2001, Chugangjam was 5% higher in cocoon yield and 8% in raw silk productivity in the 10,000 of the 3rd molted larvae, respectively, than the check variety Daesungjam.

• Journal of Sericultural and Entomological Science
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• v.42 no.1
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• pp.24-27
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• 2000

A new silkworm variety 'Yangwonjam'for both of spring and autumn rearing season is F$_1$hybrid between Jam 143, a Japanese race bred from H5R1/P8503 and Jam 144, a Chinese race from M8312/8190. This is the first both parent sex-limited larval marking variety in Korea, and which contributes to eggs production of F$_1$hybrid silkworm with saving labor. Jam 143, Japanese parent of the 'Yangwonjam'showed high GCA in pupation percentage and Jam 144, Chinese parent showed high GCA in pupation percentage and single cocoon weight. In the local adaptability test performed at 8 local areas in spring of 1998, Yangwonjam records 1% higher in pupation percentage and 5%, 4% lower in single cocoon weight, cocoon yield from 10,000 3rd molted larvae respectively than the check variety Kumokjam. Also in the resistance test against unfavorable rearing condition performed in spring of 1997, Yangwonjam records 9%, 14% lower in single cocoon weight, cocoon shell weight respectively than the check variety, but showed 1% higher in pupation percentage than check variety.

• Korean Journal of Animal Reproduction
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• v.12 no.1
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• pp.42-47
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• 1988

This experiment was carried out to investigate the sex ratio of produced lamb after artificial insemination into the cervix with spermatozoa from the top and bottom portion of ram semen separated by diluting semen a column of protein, and after implantation into the uterus with normal morulae and blastocyst cultured in BMOG-3 and Ham F-10 medium containing H-Y anbibody and complement treated with spleen and testis, respectively. All embryos developed to morulae and blastocyst were cultrued in medium under gas phase of 5% CO2 in air at 37$^{\circ}C$, 24 hrs. Estrus of ewes induced by a MAP vaginal sponge and 750 IU PMSG during the non-breeding season. The result obtained in these experiments were summarized as follows: 1. The ratio of heating, lambing, and prolificacy after artificial inseminatin into the cervix of ewes induced by a MAP vaginal sponge and 750 IU PMSG during the non-breeding season were 100%, 40% and 2.74 heads, respectively. 2. Involving 44 ewes, spermatozoa from the top of the protein column produced 23.1% male and 76.9% female lambs, while spermatozoa from the bottom of the column produced 81.3% male and 18.8% female offspring, respectively. 3. The sex ratio (male-to-female) of progeny produced after implantation with normal morulae and blastocyst cultured in medium containing H-Y antibody and complement treated with spleen and testis were 21.0%, 79.0% and 17.4%, 82.6%, respectively.

• Journal of Embryo Transfer
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• v.25 no.2
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• pp.89-92
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• 2010

We report herein the successful results of estrus induction, sperm cryopreservation and kids born by transcervical insemination of frozen-thawed semen in a Saanen goat. Flugestone acetate (FGA: 60 mg) was inserted into vagina for 15 days. The goat was intramuscularly injected with 400 IU PMSG and 200 IU hCG ($PG600^{(R)}$: Intervet, Korea) a day before withdrawal of the FGA sponge. Follicles and corpora lutea were identified on both ovaries by laparoscopy. Artificial insemination was performed 46 hours after removal of FGA sponge. The concentration of frozen-thawed semen was $3.975{\times}10^8/ml$ and 0.5 ml of frozen-thawed semen was transcervically inseminated into uterine body under anesthesia. Three kids, all females, were born 144 days after artificial insemination. This is the first report producing kids by transcervical insemination of frozen-thawed semen in a Saanen goat of which the estrus was induced by FGA sponges, PMSG and hCG during non-breeding season in Korea.

• Korean Journal of Ecology and Environment
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• v.51 no.2
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• pp.184-191
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• 2018

During the breeding season, some Eurasian Oystercatchers (Haematopus ostralegus osculans) in Yubu Island foraged in the open mudflat area nearby the breeding ground, instead of the tide water line area, main feeding site throughout the year. We found significant differences in foraging behavior and prey species diversity between the two different feeding site types. Even though the birds took more steps for most probably searching preys, their feeding success was much lower in the open mudflat area than the tide water line area. The multiple peck and boring methods were more frequently adopted to catch polychaetes on the open mudflat area, whereas the single peck method was dominant and gastropods and bivalves were main preys in the tide water line area. This study suggests that the bird shows flexible foraging strategy of shifting feeding site, foraging behavior and preys for better reproductive success.

• Journal of Animal Science and Technology
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• v.49 no.4
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• pp.443-450
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• 2007

This study was designed to investigate the seasonal variation in semen characteristics and the change of motility during semen frozen/thawed, and conception rates were observed following AI at the different times after estrus synchronization. Semen collected from March to May showed significantly lower semen quality than the other months (P<0.05) and semen characteristics (volume, total sperm and motility) were significantly higher in October. Sperm motility after thawing in frozen semen were significantly lower in non-breeding season than in breeding season (P<0.05). Conception rate after treatment of estrus synchronization and AI different time after CIDR device removal, at 60 hour was higher than those of any other times through AI but there was no significantly difference between AI times. Semen characteristics change gradually during the breeding and non-breeding season. These results were considered as a model for the use of assisted reproductive techniques for AI of deer in Korea.

• Journal of Animal Science and Technology
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• v.44 no.3
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• pp.271-278
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• 2002

This experiment was conducted to investigate the genetic and non-genetic factors affecting kid survivability in goats from birth to 90 days of age. The purebreds had lower survivability than the crossbreds, with significant (p$<$0.05) difference amongst themselves for the age of 31 to 90 days. The locational effect on survivability was insignificant for all the periods except 16 to 60 days (p$<$0.05) of age. The sex and birth type also had significant (p$<$0.05) effect on survivability for all the periods except 0 to 7 days of age. The survivability was found to be significantly (p$<$0.05) higher for kids born in summer season followed by those born in winter and rainy season. Milk produced by the does were significantly (p$<$0.05) affected on the survivability of kids during the period from 16 to 60 days of age. The survivability of kids were highest and lowest having milk yield of doe found to be 400-600 g/day and 80-200 g/day, respectively. Birth weight had significant (p$<$0.05) effect on survivability for all the stages of growth up to 90 days of age. Survivability was positively correlated with does’ milk yield as well as kids birth weight. Interactions of sex with location or birth type were significant (p$<$0.01 and p$<$0.05, respectively) though interaction between sex and genetic group was insignificant.