산란계의 교잡육종에 관한 연구

오봉국,여정수 ( Bong Kug Ohh,Jung Sou Yeo ) 한국축산학회 1979 한국축산학회지 Vol.21 No.4

This experiment carried out to identify combining ability and genetic sources of 5 purebreds A, B, C, K, N strains through crosses among them. Those data were collected during 45 weeks from 19th, May 1977 to 30th, March 1978 at Poultry Breeding Farm, College of Agriculture, Seoul National University, and experimental stocks used were 1,345 purebreds and 519crossbreds. Theres was evidence to indicate that for all characters except viability these data could investigate the crosses to be better than the parents from which they were derived. Phenotypic performances of AK, BK, CK strains which were derived from K-male, and AK, AN strains from A-female could be measured as superior general combining ability of A and K strains in egg production. Sexual maturity day of BK crossbred shortened 12 days compared with mean performance of it`s parent. This considerable result proposed satisfactory specific combining ability of B to K strain. AN and BN crossbreds which were produced from N line, genetically small egg lager, laved smaller egg than others. In body weight, crossbreds of N-male were observed as h yaw birds which might require more feed for body maintenance. As these results utilization of N strain in breeding of layer seemed to be negligible source. Reciprocal cross of C and K strain seemed to show the sex-linkage effect of K strain in egg production and maternal effect of C strain in egg weight. In general, additive effects were the most important for egg weight and body weight but nonadditive effects for egg production. Using the above identifications which were satisfactory general combining ability of A and K strains, and specific combining ability of B strain to K strain, continuos genetic improvement of non-additive effect by crosses of those strains can be expected to be considerable achievements.

C- banding 에 의한 닭의 heterochromatin 다형현상

오봉국(B . K . Ohh),손시환(S . H . Sohn),여정수(J . S . Yeo) 한국축산학회 1990 한국축산학회지 Vol.32 No.1

C-banding regions were detected in almost all macrochromosomes of chicken. However the variability of C-banding in mitotic cells existed among the embryos, among cells from the same embryos, and between homologues. These variable results were thought to be the consequence of differing amounts of DNA denat uration and extraction within a given C-banding region. Constant C-bands were located at telomeric region of the Z chromosome and the whole regions of W chromosome. Most of C-bands were located at centromeric and telomeric in the 1st, 2nd, 3rd, 4th and 5th chromosomes. In addition, the relative amounts of heterochromatin in each macrochromosome were estimated at 12∼19%. These amounts were similar to the contents of highly repetitive DNA in chicken genome.

한우 염색체의 Constitutive Heterochromatic Banding ( C- banding ) 양상

오봉국(B . K . Ohh),여정수(J . S . Yeo),손시환(S . H . Sohn),홍영호(Y . H . Hong) 한국축산학회 1991 한국축산학회지 Vol.33 No.5

Heparinized peripheral blood was cultured according to the routine method. For inducing the metaphase plates colcemid was added to the cultures at 1.5 hr before harvesting and chromosomes preparations were made by the conventional air-drying procedure. For C-banding, the best result was obtained by Sumner`s(1972) banding technique using by acid, alkali, and salt treatment. Therefore. the results of the study were described as follows; l. The chromosome number and morphological characteristics. Total number of Korean Native Cattle(Han-Woo) chromosomes was 60(2n), 30 pairs, including the sex chromosome XY or XX and 58 autosomal chromosomes. The autosomal chromosomes and X, Y sex chromosomes were characterized acrocentric, submetacentric and metacentric, respectively. The longest pair of 1st autosome and sex chromosomes usually can be identified by morphological characteristics. However, the rest of 56 autosome; showed a little difference only in length. Therefore, identifying homologous chromosome pair was nearly impossible. 2. The analysis of C-banding chromosomes it Korean Native Cattle. C-banding regions were discovered in nearly all SR autosome`s centromere position but the X chromosome showed interstitial bands, that is, moderately centromeric block which extends into both chromosome arms. The Y chromosome was usually rather dark throughout. and was considered to have an effects only on sex determination. Relative amounts of the constitutive heterochromatin were measured and the percentage of heterochromatic regions of each chromosomes were 20-40%. Banding patterns depend on the chromosomal proteins, degree of DNA contraction, salt condition and storage period of the slides. Consistent banding patterns, therefore, would not appear in the same individual cells. However. heavy heterochromatin showed consistent and continuous banding patterns. The best analysis for C-banding requires repetitive experiments and statistical analysis for the amounts of heterochromatin and regions of the appearence. In addition, it was suggested that biochemical interpretation be needed for C-banding pattern for the study of genetic composition and action.

육용 종계의 주요 경제형질에 대한 유전변이 추정에 관한 연구 1 . 양면교잡에 의한 육용 종계 체중의 유전변이 추정

최광수,오봉국,여정수 ( Kwang Soo Choi,Bong Kug Ohh,Jung Sou Yeo ) 한국축산학회 1980 한국축산학회지 Vol.22 No.6

The study was conducted to obtain some genetic information for developing superior broiler breeder stock. Genetic variations were estimated with 997 progenies of $quot;4 × 4$quot; dialled crosses. The progenies were raised at the Livestock Experimental Farm, College of Agriculture, Seoul National University from March, 1974 to June, 1975. Body weights at 8, 24 and 64 weeks of age were investigated and analyzed into additive gene effects, dominance effects and heritabilities with Hayman`s model. The estimates of these effects were made with $quot;4 × 4$quot; dialled tables of three White Plymouth lock lines (RF, SF, TF) and a line of White Cornish (TM), and again with $quot;3 × 3$quot; diallel tables of three White Plymouth Rock lines in order to compare the effects from breed-crosses and line-crosses of the same breed. In body weights at the ages of 8 and 24 weeks, the genetic variation due to additive among parental lines showed significant differences in both cases of breed-crosses and line-crosses. However, dominance effects appeared in case of breed-crosses, and the effects of overall dominance and line dominance slowed significant differences. No significant differences were observed in genetic variation on body weight at the age of 64 weeks. Heritability estimates for the body weights at the age of 8, 24 and 64 weeks were 0.77, 0.74 and 0.14 in the White Plymouth Rock ; and 0.49, 0.35 and 0.08 in the crossbred of White Plymouth Flock and White Cornish, respectively.

난용계의 주요경제형질에 대한 상가적 ( 相加的 ) 및 모체유전효과의 상관계수 추정

여정수,오봉국 ( Jung Sou Yeo,Bong Kug Ohh ) 한국축산학회 1983 한국축산학회지 Vol.25 No.4

Data from the 2718 birds of two Leghorn populations for three generations were analyzed to determine the genetic correlations between direct effects(γXoYo), maternal genetic effects (γXmYm) and direct-maternal genetic effects (γXoYm, γXmYo) for X and Y traits. It was found that in A line egg production will be improved according to light initial body weight, increase of egg weight highly correlated with body weight will be higher than the expected estimates on the basis of γXoYo, and egg production improvement after 43 weeks of age will derive the decrease of egg weight in the causes of negative γXmYo between egg number and egg weight. In D line, highly negative coefficient in yXmYo between body weight and egg number, body weight and egg weight, and egg number and egg weight will provide increase of egg number from lighten body weight, while correlated response between egg weight and body weight will be biased below the expected estimates and also decrease of egg weight dependent on increased egg number will be less than the expected estimates.

초산시 체중이 주요경제 형질에 미치는 영향

여정수,오봉국 ( Jung Sou Yeo,Bong Kug Ohh ) 한국축산학회 1978 한국축산학회지 Vol.20 No.3

This experiment was conducted to investigate the optimum body size at 18 weeks of age which would relate to other economic characters in layer. Data of first egg day, egg production, egg weight, body weight, feed efficiency, and adult mortality were collected at Poultry Breeding Farm, College of Agriculture, Seoul National University from March 25, 1976 to 7une 2, 1977. The results obtained were as follows: 1. The first egg day was significantly correlated with body weight at sexual maturity. Heavy body weight groups showed relatively earlier in first egg days than low body weight groups. 2. Egg production didn`t show close relation to body weight but there was a tendency that the relatively lighter body weight groups laid more eggs than higher groups. In this strain, optimum body weight at sexual maturity for egg production seemed to range from 1,275g to 1,425g. 3. In egg weight of this strain there was evidently critical point between heavy and light group at 1,425g in body weight at sexual maturity. Egg production, growth rate and sexual maturity were suggested as a second factors to influence egg weight. 4. Body weight at 18 weeks of age was highly correlated with body weight during laying period. 5. Feed requirement per ㎏ eggs produced showed highly positive correlation with initial body weight. Birds weighing from 1,275g to 1,325g at sexual maturity seemed to bring the best feed efficiency. 6. During laying period viability of the lightest group weighing below 1,275g at 18 weeks of age was observed relatively low, but geneal tendency between body weight and viability was throught to be flexible.

난용계 모체유전효과를 이용한 유전변이 추정에 관한 연구

여정수,오봉국 ( J . S . Yeo,B . K . Ohh ) 한국축산학회 1982 한국축산학회지 Vol.24 No.1

Data from the 1,131 birds of synthetic population (A) and 1,587 birds of selected population (D) for three generations were analyzed to determine the different components; additive variance, maternal genetic variance and covariance between additive-maternal genetic effects of economic traits. Coefficients of variations of mean performances in synthetic line were decreased and those of selected line were nearly constant year by year. It was found that maternal genetic variances were important in all traits except egg weights before 43 weeks of age in both lines, showing greater values in synthetic line than in selected line. Correlations with additive-maternal genetic variances, when present, were highly negative in all traits which seemed to influence to derive difference between heritabilities from sire and dam variance components through sib analysis in the absence of dominant effect. Adjusted heritabilities included additive variance, maternal genetic variance and covariance between additive-maternal genetic effects were large in body weights at different age and small in egg numbers and initial egg weights of both lines.

닭(gallus domesticus)의 經濟形質 改良을 위한 染色體 分染分析과 標識因子의 究明에 관한 硏究 Ⅱ. 卵用種의 系統間의 比較

Jung Sou Yeo(呂政秀),Bong Kug Ohh(吳鳳國),Bong Bo Seo(徐奉甫) 한국육종학회 1985 한국육종학회지 Vol.17 No.1

This experiment was carried out to identify the differences of genetic materials as genetic marker for the four strains of egg type breed. The differences of strains of egg type chick were as follows. It was chracterized with strain A to show less band at distal part of chromosome #3 and dark band at centromere of #4-q. More bands at distal part of #1-q than others was the marker of strain K. In strain M, less band at #2-p and non-band at distal part of #Z-q were observed, and dark band at centromere of Z chromosome like the feature of meat type chick was the chracteristics of strain S.

닭(gallus domesticus)의 經濟形質 改良을 위한 染色體 分染分析과 標識因子의 究明에 관한 硏究 Ⅰ. 品種間의 比較

Bong Kug Ohh(吳鳳國),Jung Sou Yeo(呂政秀),Bong Bo Seo(徐奉甫) 한국육종학회 1985 한국육종학회지 Vol.17 No.1

This experiment was carried out to identify the differences of genetic materials as genetic marker for the three chick breed. The characteristics of chick chromosome were as follows. The 10 pairs chromosomes generally identified by morphology vary in size from about 7 ㎛ to small dot. It was identified that chromosome #1 and 2 were grouped as sub-metacentric, #3 was telocentric, #4 was as acrocentric and #5 was as metacentric and sex chromosome Z. Residual as intermediate chromosomes is found as acrocentric for #6, #7, #8, #10 and sub-metacentric for #9. Metacentric sex chromosome W was similiar size of the #9. The identification of the egg type, meat type, and dual purpose type chicken was also as follows. Egg type chick was featured by the less band at distal part of #1-p and #4-q than others. Dark band adjacent to centromere of meat type chick was found as the specific marker and in dual purpose chick was more bands at #1-p, #2-p, and central part of #3 than the other breeds.

난용계에 (卵用鷄) 있어서 상가적 (相加的) 및 모체유전 효과를 이용한 선발지수 추정

여정수(Jung Sou Yeo),오봉국(Bong Kug Ohh) 한국축산학회 1984 한국축산학회지 Vol.26 No.1

The data from the record of 1131 birds of synthetic population (A line) and 1587 birds of selected population (D line) through 3 generations (1977-1980) were used for the estimates of expected genetic gain by selection indices based on the additive effect only and maternal and additive effects. It was found through Hazel`s method considered the only additive effect that in both lines the first egg day and egg weight at 43 weeks of age were decreased while egg number to 43 weeks of age was increased, and body weight at 43 weeks of age was slightly decreased. And A line showed more satisfactory genetic changes compared with D line except body weight. Expected genetic gains in A line based on genetic parameters estimated using additive and maternal genetic effects simultaneously were the most significant for increase of egg number among the four traits studied and egg weight was 2.50g heavier than performance of this generation, while body weight and the first egg day were decreased, which were considered most desirable in genetic changes of layer. In line D genetic gain of egg production could be achieved through maternal genetic effect with maintaining body weight nearly constant. And major profitable egg weight was decreased by 0.87g lower than that of this generation, and the first egg day was also shortened. According to above results genetic improvement using the additive and maternal effects may be achieved more desirable than that using the additive effect only.