• The Korean Journal of Malacology
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• v.30 no.4
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• pp.415-419
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• 2014

Inbreeding depression may be an avoidable phenomenon for abalone culture. However, only a few studies were carried out on inbreeding depression. In the present study, to demonstrate inbreeding depression in growth trait of Pacific abalone, H. discus hannai, inbreeding and outbreeding families were produced in 2010. Inbred and outbred families from each experiment were reared in same tank until 10 month for the same breed environment. The individual of inbred and outbred were distinguished by paternity test using microsatellite DNA. The shell length between inbred and outbred families was compared. At the results, significantly higher shell length was observed in the outbred families at 10 mon (P < 0.05). These results indicate that inbreeding depression is obviously observed in growth traits in the first generation of full-sib family of the H. discus hannai.

• Journal of Life Science
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• v.17 no.11
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• pp.1477-1481
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• 2007

The mating systems of natural populations of Vicia tetrasperm in Korea were determined using allozyme analysis. The result suggests that V. tetrasperm is low rates of outcrossing or mix-mating outcrossing (self-fertilization, s < 0.5). At the population levels, the values of inbreeding coefficient of ten populations in Korea varied from 0.131 to 0.176, giving an average 0.154. For ten natural populations, multi-locus estimates of outcrossing (tm) was 0.333 across fifteen polymorphic loci, with individual population values ranging from 0.269 to 0.423. The differences between the tm and ts values were not close to zero (tm - ts > 0.154), indicating that biparental inbreeding was significant in the loci. The reason for relatively low outcrossing rates of some populations could be attributed to extensive consanguineous mating and isolation of flowering mature plants. Although heterozygote excess was observed in one natural population, most populations exhibited varying degrees of inbreeding and heterozygotes deficit. Thus, selection against homozygotes operated in the progeny populations throughout the life cycle.

• The Korea Swine Journal
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• v.8 no.11 s.87
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• pp.44-49
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• 1986

• 한우개량
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• no.2 s.23
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• pp.20-22
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• 2000

3월 이후는 번식에 적합한 계절이므로 많은 인공수정이 실시될 것이다. 그러나 정액 및 교배대상우의 혈통정보를 알고 있는 농가가 그리 많은 것은 아니지만 인공수정사, 한우개량농가육성사업 담당자 및 암소의 혈통을 알고 있는 번식농가가 쉽게 근친을 피할 수 있는 정액선정요령을 게재한다.

• Korean Journal of Poultry Science
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• v.17 no.4
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• pp.255-268
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• 1990

This study was carried out to investigate the time-trends of genetic parameters of the dosed flock population which selected for improving egg production. Data for two layer pure lines, Line-W (Single Comb White Leghorn) and Line-B (brown layer) which have been maintained at the Mani Breeding Farm were collected from 1980 to 1985 during 5 generations. The effective number of parents per generation ranged from 148 to 366 in Line-W and 85 to 355 in Line-B, and the cumulative expected inbreeding coefficients during 5 generations of selection were 15％ and 1.6％. So inbreeding could not be considered a critical factor on estimating the genetic parameters, heritabilities and genetic correlations Heritabilities of EN 300 and EN 400, primary two selected traits were significantly decreased during 5 generations but the estimates of the other 03its not showed the consistent decreasing pattern significantly. No time trends of probable consequence were evident in the genetic correlation coefficients of the traits studied. The reason for that situation was attributed to the fact that selection was conducted for multiple objectives and the relative importance of selection for the studied traits were not consistent by generations.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.31-31
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• 2002

건강보조식품의 홍수와 함께 우유보다 소화흡수가 좋고 건강식을 즐겨하는 현대인들의 취향에 발맞추어 상대적으로 유량과 산육성이 좋은 외래산양의 유입이 급속하게 늘어남으로써, 일부 재래산양 사양 농가들은 생산성 향상을 목적으로 재래산양과 외래산양의 무분별한 교배를 시키므로써 재래산양의 유전자원의 보존문제가 대두됨과 동시에 재래산양의 개량의가속화, 근친교배에 따른 문제점, 계절번식에 따른 산자생산의 한계 등은 재래산양의 인공수정에 대한 깊이 있는 연구로 이어져야 하겠기에 본 연구에서는 38 두의 재래산양을 공시하여 실험한 결과 여름과 겨울에 채정한 정액보다는 봄가을에 채정한 정액의 량이 2.0㎖로 여름과 겨울보다 많았으며, 정자농도는 봄에 21.0×10/sup 8//㎖로 가장 짙었고, 총정자수는 봄에 42.0×10/sup 8/로 가장 많았으며, 운동성은 가을에 90(motility)로 가장 좋았다. (중략)

• The Korean Journal of Mycology
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• v.2 no.1
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• pp.31-33
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• 1974

The four stocks of Lentinus edodes (Berk.) SING.-1-3, 16-3, 5NG2, 5NG3 were used as mating materials. As a result of full stock mating pattern for four stocks, all of mating types formed clamp connection but degrees of formation of clamp connection and period required for the formation were somewhat different among all of the mating types. In the mating of two New Guinean stocks-5NG2, 5NG3-, the mycelial growth and the formation of clamp connection was comparatively reduced.

• Journal of Veterinary Clinics
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• v.30 no.5
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• pp.384-386
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• 2013

A two-year-old, female English bulldog was referred for breeding by artificial insemination with frozen semen of male English bulldog, a litter of female bulldog's grandfather. Intrauterine artificial insemination was done two days after the ovulation day. Sperm was evaluated after thawing by computer assisted sperm analyzer, and its motility was 89.8% with normal shape. Pregnancy bearing eight fetuses was diagnosed by ultrasonography and radiography. Cesarean section was performed sixty days after the artificial insemination. Eight pups were delivered with safe, but the entire pup had abnormalities including severe bow-legged malformations, cleft lip, cleft palate, and enlarged cranial part.

• Korean Journal of Agricultural Science
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• v.42 no.2
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• pp.141-149
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• 2015

The data of Duroc swine species that were born from 2000 to 2014 excluding missing ones collected by Korea National Institute of Animal Science were used in the present study. After removing missing data we used 9756 of productions data and 1728 of reproductive reference of breeding research to study the level of inbreeding and to investigate the impact on the reproductive traits, production traits. The correlation of reproductive traits and inbreeding coefficient are -0.07, -0.08 for total number pigs born, number of pigs born alive respectively and birth weight per litter is -0.10, number of pigs born alive per litter to 21days is -0.06 and body weight per litter to 21days is -0.09. The correlation coefficients of the inbreeding coefficients of reproductive traits are shown within 10% with negative correlation (P < 0.05). Days of 90kg and Backfat in the correlation coefficient and inbreeding coefficient production traits were not observed significant correlations, Average daily gain was investigated by the positive correlation of 0.05. According to the above results, the inbreeding level gave a negative effect on the improvement of the breed traits, investigating a relatively high compared to a negative effect on other traits. But overall correlation degree is less than 10% was observed. This inbreeding coefficient has not been clearly observed due to degeneration of the average inbreeding coefficients of these generations was maintained within 10% of the population. The scale of the experimental group was about 150 degree pig husbandry is very small compared to the advanced countries. However, the level of inbreeding in the population group with the appropriate mating combinations is maintained below 10% of population is thought to be small and can minimize the effects of inbreeding degeneration. further testing utilizing this selection is constantly considered to be necessary.

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.578-587
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• 2015

Nuclear SSR (nSSR) and chloroplast SSR (cpSSR) markers were analyzed to assess the parameters of mating system in seed orchard, such as outcrossing rates, the number of potential pollen contributors, paternal contribution rates, degree of pollen contamination, and biparental inbreeding ($t_m-t_s$). In 2006, 2007, seeds were collected from the seed orchard of Pinus densiflora, established in 1977 at Anmyeon island. Estimates of outcrossing rates ranged from 94.9 to 100% (mean 98.9%) in 2006 and from 91.2 to 100% (mean 97.7%) in 2007 on the basis of the analysis of cpSSR haplotypes and from 90.3 to 100% (mean 95.9%) in 2006 and from 81.6 to 100% (mean 95.3%) in 2007 on the basis of the analysis of nSSR genotypes. By cross checking of both DNA markers, mean cumulative outcrossing rates of 100% and 98.9% were estimated in each year. Mean contamination rates were estimated as 48.9% and 42.4%, respectively. On the basis of cpSSR haplotype observed in each seed, paternal contribution rates (the number of pollen contributors) were estimated as 0.458 (mean 16.2) in 2006 and 0.512 (mean 14.8) in 2007. In conclusion, considering pretty high level of outcrossing rates observed in a seed orchard, there might be little to be influenced by inbreeding depression for genetic potential of the seeds induced by selfing. Estimates of the mating system parameters obtained from the two reproductive years were not statistically different, which revealed stable genetic quality of seeds produced in different years. Observed results from this study may provide useful information for the management and establishment of the seed orchard of the progressive generation.