• Journal of Animal Science and Technology
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• v.49 no.6
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• pp.699-710
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• 2007

This study was conducted to estimate the genetic parameters and their relationships with weight traits of the steers and bulls in the Hanwoo population. The data used were weights and weight gain of performance and progeny test from 6,024 heads of Hanwoo. Data of performance test consisted of total 3,737 heads raised from August, 1989 to September, 2005. The number of the records of progeny test was total 2,287 heads from August, 1996 to June, 2004. The heritabilities and correlations for the body weights at the ages of 6 months, 12 months and 24 months and average daily gain were estimated by DFREML. Overall means and standard deviations of body weights at 6 and 12 months of age and average daily gain(ADG) from the data of performance test were 181.72±30.22kg, 351.48±40.24kg, 998.07±153.84g, respectively. Overall means and standard deviations of body weights at 6, 12, and 24 month of age and ADG from the data of progeny test were 169.18±32.82kg, 229.37±44.57kg, 570.45±64.36kg and 739.41± 172.14g, respectively. The heritability estimates of the body weight at 6, 12 month and ADG from the performance test were 0.54±0.06, 0.60±0.06 and 0.23±0.04, respectively. The heritability estimates of the body weight at 6, 12, 24 month and ADG from the progeny test were 0.80±0.08, 0.50±0.07, 0.46±0.07 and 0.07±0.03, respectively.

• Journal of Animal Science and Technology
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• v.48 no.6
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• pp.759-766
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• 2006

This study was conducted to investigate the genetic correlations among the traits used to select young bulls and proven bulls in Hanwoo Performance and Progeny Test Program in Korea. For the estimation of heritabilities and correlations among the growth traits of bulls and carcass traits of progeny steers, 2,532 records of performance tested bull calves and 1,819 records of progeny tested steers were collected from Livestock Improvement Main Center (LIMC), National Agricultural Cooperative Federation (NACF). Fixed effects of mixed model for each traits were selected by using stepwise regression analysis and prior values of variance components were estimated by MTDFREML. The prior values of variance components were estimated with pairwise 2 traits model followed by single trait analysis. The estimated heritability of backfat thickness(BF), dressing percentage(DP), loin-eye muscle area(LMA), marbling score(MS) and weight at 12 months(WT12) was 0.51, 0.32, 0.27, 0.33, 0.50 and 0.26, respectively. Genetic correlation of WT12 of bull calves with backfat thickness, carcass weight and loin-eye muscle area of steers was positive correlation as 0.05, 0.35 and 0.21, respectively. However genetic correlation of WT12 with DP and MS showed negative correlation as 󰠏0.09 and 󰠏0.27, respectively and these negative genetic correlations implies that bulls that may be superior in carcass traits can be lost at the first step of selection and current selection method should be modified to solve this problem.

• Journal of Aquaculture
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• v.9 no.2
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• pp.125-132
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• 1996

A study was carried out to test sex ratio of the progeny that were induced by the artificial fertilization between normal female and gynogenetic diploid eggs and sex-reversed gynogenetic diploid male sperm. Sex reversed gynogenetic diploid males were produced successfully in gynogenetic diploid female by immersion treatment with $17{\alpha}$-methyltestosterone at the concentration of 10 pub from $13.5{\pm}0.22$ mm to $57.6{\pm}5.1$ mm in total length. In $F_1$ progeny test, matings between normal females and sex-reversed gynogenetic males were not produced all female, but matings between gynogenetic diploid females and sex-reversed gynogenetic males were produced all female populations in six out of eight groups and two lots produced $96.9\%$ and $95\%$ female. These data showed that all-female populations were produced by crossing between gynogenetic diploid female and sex reversed gynogenetic diploid male.

• Journal of Radiation Protection and Research
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• v.26 no.4
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• pp.399-408
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• 2001

The variation characteristics of radon concentration, equilibrium equivalent concentration and equilibrium factor in some houses and laboratory buildings have been studied. The variation of equilibrium factor and the unattached fraction of radon progeny with ventilation condition have been also estimated. The averages of radon concentration, equilibrium equivalent concentration and equilibrium factor were $30\;Bq\;m^{-3},\;19.6\;Bq\;m^{-3}$ and 0.65 in seven houses, while $55.0\;Bq\;m^{-3},\;31.9\;Bq\;m^{-3}$ and 0.58 in three laboratory buildings, respectively. The diurnal variation of radon concentration, equilibrium equivalent concentration and equilibrium factor in indoor showed a typical pattern that the radon concentration, equilibrium equivalent concentration and equilibrium factor increased at dawn and morning, while decreased at midday and evening. While the equilibrium factor rate deceased in the indoor environment which was well ventilated, the unattached traction of radon progeny increased. The equilibrium factor was in proportion to air pressure and humidity of indoor, whereas in Inverse proportion to temperature.

• Journal of Embryo Transfer
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• v.29 no.3
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• pp.289-296
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• 2014

The pedigree information and race records of 1,000 m finishing time of Jeju race horses at KRA were used to study the effect of amount of pedigree information and parental misidentification on the estimates of genetic parameters. The modified data sets were made at the range of 2.5 to 25% parental misidentifications or loss of parental information of individuals with an increment of 2.5 percent. For each incremental level, 20 randomly replicated data sets were obtained and analyzed by single-trait analysis with a DF-REML(AI) algorithm. As the rate of misidentification increased or the amount of pedigree information decreased, the estimates of fraction of additive genetics variance component gradually decreased almost linearly (p<0.05), while the estimated fractions of error variance and permanent environmental variance components gradually increased for the finishing time. Regression coefficients of the percentage amount of both parents' information loss and incorrect pedigree information on additive genetic variances were -0.079 and -0.114, respectively (p<0.01). The estimate of heritability decreased by 0.92% for one percent loss of both parents' information and 1.39% for one percent increase of both parental misidentifications of progeny (p<0.01). For the consideration of probable incorrect and missing parent information of progeny in this early population of Jeju horses, the estimates of additive genetic parameters would be biased downward about ten percent. This results indicate that the amount of pedigree information loss and misidentification of progeny would severely affect estimates of genetic parameters and would reduce genetic gains for selection in Jeju horse population.

• Korean Journal of Plant Resources
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• v.28 no.2
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• pp.259-262
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• 2015

We performed the following experiment to increase the development of shoots in the in vitro culture of hybrid progeny. MS medium was used as the base medium; cytokinins BA at a concentration of 2.0, 3.0, or 5.0 ㎎/L and TDZ at a concentration of 0.2, 0.3, or 0.5 ㎎/L were added to the in vitro cultures. For the FO progeny, the shoot development rate was highest of 18% with 2.0 ㎎/L BA, at 18%, and 3.0 ㎎/L and 5.0 ㎎/L BA resulted in a lower rate of 12%. TDZ addition tended to identical or similar results to that of the control media. For the FA progeny, addition of TDZ tended to lead to a higher shoot development rate and was superior with 0.3 ㎎/L treatment. However, the addition of BA to the media resulted in a shoot development rate between 14.3% and 15.7%, similar to that of the control.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2000.05a
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• pp.128-128
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• 2000

• Proceedings of the Plant Resources Society of Korea Conference
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• 2000.10b
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• pp.29-29
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• 2000

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.2
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• pp.139-143
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• 2004

It was investigated whether developmental characteristics of foundation queens of Bombus ignitus collected in the 4 localities in Korea would be affected by the first oviposition days of them. The first ovipostion day was classified as 1-4 days (immediate early), 5-6days (early), 7-10 days (delayed early), 11-20 days{medium), 21- 40 days (late), and above 41 days (very late). The queen that had the early first oviposition day, i.e., laid eggs so early after starting to be raised indoors, showed much higher rate of colony foundation and progeny-queen production and much shorter period of colony foundation and worker emergence. Besides, the numbers of worker and progeny-queen emerged from the queen that had the early first oviposition day were higher than those of the queen that had the late first oviposition. In results, the queen that had the early first oviposition day could make colony stronger and could make colony formation period shorter, therefore, the first oviposition day of foundation queen was proved to be a criterion for the selection of super colonies when B. ignitus is raised indoors.

• International Journal of Industrial Entomology and Biomaterials
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• v.11 no.2
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• pp.81-86
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• 2005

The mode of transmission, effect on fecundity, hatching and tissues specificity of a microsporidian $(Lb_{ms})$ recovered from Lamerin breed of the silkworm Bombyx mori L. was studied and compared with standard strain Nosema bombycis. Peroral inoculation of $Lb_{ms}$ or N. bombycis to zeroday of $4^{th}$ instar larvae of silkworm was the most suitable method for producing information on development of stage specific mortality, pupation and obtaining infected adults for transovarial transmission studies. It was observed that pupal mortality, the percentage of moths emerged and the percentage of moths infected were significantly high in N. bombycis infected batches as compared $(Lb_{ms})$ in all the three tested breeds of the silkworm. However no significant difference was observed in larval mortality. The fecundity and hatchability was not affected significantly in $(Lb_{ms})$ infected adults, however significant reduction in egg production, fecundity, hatchability and increased egg retention was observed in mother moths infected with N. bombycis. The $(Lb_{ms})$ is transmitted both horizontally and vertically at lower rate due to its low rate of proliferation. The trans ovarial transmission of $(Lb_{ms})$ to the $F_1$ progeny generation through eggs averaged only $61.33\pm5.10\%$ whereas N. bombycis was transmitted at $100\%$. The $(Lb_{ms})$ had low oral infectivity and low transovarial transmission in silkworm B. mori.