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.

계육생산을 위한 부로이라종계의 육종개발에 관한 연구 ( 제2보 )

오봉국 ( Bong Kug Ohh ) 한국축산학회 1976 한국축산학회지 Vol.18 No.6

This study was carried out to improve broiler production arid to estimate a genetic value, and to select superior broiler breeder stocks by means of crossbreeding under domestic feeding and management conditions. Selection of superior stock in female lines: The data used in the study were the records of 18 single crosses produced by dialled cross of 4 strains of White Plymouth Rock and one strain of White Cornish, and added one strain of imported commercial parent stock. A total 1,283 chicks of crossbreds and purebreds mere used in this experiment. The results obtained in the study are summarized as follows; (1) The average date of sexual maturity was 193 days and the earliest sexual maturity was 185 days (O strain) and the latest sexual maturity was 206 days (S stain). The crossbreds had 8 days earlier sexual maturity than purebreds. (2) The average body weight at 24 weeks of age was 2,498g and the highest body weight was S strain (2,712g), and the lowest body weight was A strain (2,238g). There was no significant difference between crossbreds and purebreds, and between average body weight and recommanded body weight at 24 weeks of age. (3) The average adult body weight at 60 weeks of age was 3,625g and the highest body weight was 3,885g in S strain, and the low est body weight was 3,496g in A strain. In adult body weight for laying period was normally maintained body weight compared with breeder pullet feeding recommandations. (4) With respect to the laying hen viability the crossbreds were superior to the purebreds. The crossbred had about 5.1 percent lower mortality than the purebred. The death of the laying hens were due mainly to Lymphoid leukosis Complex. (5) The average hen-day egg production from 24 to 64 weeks of age was 51.60 percent and the highest egg production strain was T crossbred (65.04%), and the lowest egg production was B purebred (39.15%). The hen-day egg production appeared to be the most consistent of hybrid vigor. The crossbred averaged about 8.5% higher than the purebreds. The hen-housed average egg production was 144 eggs and the crossbreds were superior to the purebreds. The crossbred had about 20% higher egg production than the purebreds. In statistical analysis for combining ability in egg production, general and specific combining ability were significant. Consequently it seems to be important to be select dam and sire lines. The highest hen-housed egg production was 184 eggs in T crossbred. (6) In egg weight, the average egg weight was 61.96g grams and the highest egg weight strain was F crossbred (63.98grams), and the lowest egg weight strain was T crossbred (59.72grams). The crossbreds were superior to the purebreds in egg weight. (7) The average conversion of feed into egg production was 4.56㎏ and the lowest feed requirement strain (5.91㎏). Feed requirement of S strain which was imported broiler P.S. was 4.86㎏ of feed to produce per kilograms of eggs. With respect to the feed efficiency the crossbreds were superior to the purebreds. The crossbred had about 18 percent lower feed requirement than the purebreds. (8) In economic analysis of broiler breeder stock, the average of net income of per laying hen was 1,318won and the highest net income was T crossbred (2,552 won), and the lowest net income was B strain (-164 won), The average net income of S strain was 966 won. With respect to the cost of per egg production, the averages of per egg production cost was 33won and the lowest production cost was T crossbred (25.54 won). Egg production cost of S strain which was imported broiler breeder stocks was 35.44won and the S strain needed more cost to produce per egg was 9.79 won compared with the T strain. In the conclusion, the average performance of selected dam lines O and T strains was superior than the imported parents stock in the over all results of this experiment. A comparison of relative performance between selected superior female breeders and Arkansas meat performance e

계육생산을 위한 부로이라종계의 육종개발에 관한 연구 ( 제1보 )

오봉국 ( Bong Kug Ohh ) 한국축산학회 1975 한국축산학회지 Vol.17 No.1

This study was carried out to improve broiler production and to estimate a genetic value, and to select superior broiler breeder stocks by means of crossbreeding under domestic feeding and management conditions. The data used in the study were the records of 18 single crosses produced by diallel cross of 4 strains of White Plymouth Rock and one strain of White Cornish, and added one strain of imported Pilch parent stock. A total of 1,283 chicks of crossbreds and purebreds were used in this experiment. The results obtained in this study are summarized as follows: (1) Average viability of brooding and growing periods were 98.21 percent and 99.13 percent respectively and there was no significant difference between purebreds and crossbreds. In statistical analysis of combining ability, the C strain used as sire line and B strain used as dam line had about 2∼3 percent higher mortality than the other strains. The death of the chicks were due mainly to paralysis, and catarrh of crop. (2) With respect to the laying hen viability the crossbreds were superior to the pure breds. The crossbred had about 2.5 percent lower mortality than the pure strains. The death of the laying hens were due mainly to Lymphoid leukosis complex. (3) Average body weight at 8 weeks of age was 1, 399 and the highest body weight at 8 weeks of age was S strain (1,555g) and N strain (1,519g). The gain of body weight to 8 weeks of age appeared to be the most consistent of hybrid vigor. The crossbred averaged about 63g heavier than the purebreds. In statistical analysis for combining ability in the gain of body weight, general combining ability and maternal effect were significant. Consequently it seems to be important to select dam line. (4) In growth rate for grow ing period, crossbreds were normally developed compared with breeder pullet in body weight and feed recommendations. Average body weight at 12 weeks of age, 16 weeks of age and 20 weeks of age were 1,563g, 1,798g, and 2,048g, respectively. (5) The average feed conversion at 8 weeks of age was 2.49 and the highest feed efficiency was 2.42 (N crossbred) and the lowest feed efficiency was 2.55 (B crossbred). There was no significant difference in feed conversion between purestrain and crossbreds.

계육생산을 위한 부로이라 종계의 육종개발에 관한 연구 ( 제3보 )

오봉국 ( Bong Kug Ohh ) 한국축산학회 1977 한국축산학회지 Vol.19 No.5

The data used in the studies were the records of 45 crosses produced by 3 way cross of 6 strain of fatherline and 7 strain. of mother line, and added 3 strains of imported commercial broiler stock. A total 3,375 chicks of crossbreds were used in this experiment. The results obtained in the study are summarized as follows: (1) Average chick viability was 95.66% and the highest viability was(W×T) strain(98.73%), and the lowest viability was Ym strain(93.33%). There was no significant difference in viability between superior crossbreds and imported broiler stocks. (2) Average body weight at 8 weeks of age was 1,700g and the highest body weight in male lines was Wm strain(1,785g) and the lowest body weight was Xm(1,616g) strain. There was no significant difference between female line and between selected crossbreds and imported broiler stocks on 8 weeks body weight. In statistical analysis in male lines there was significant difference between sire lines. consequently it seems to be important to select sire line. (3) With respect to feed conversion at 8 weeks of age the average feed requirement was 2.26㎏ and the highest feed conversion strain was WY strain(2.17㎏), and the lowest was Xm strain(2.35㎏) in sire lines. In statistical analysis of feed requirement, there was significant difference between sire lines. It seems to be important to select sire line. (4) In point spread at 8 weeks of body weight and feed conversion, the average of point spread was 147.67% and the highest point spread was 177% in imported broiler stocks (5) In carcase percentage was WX strain(86.58%) in sire line, and H strain(86.0%) in dam line. The average of carcase percentage was 85.64% in imported broiler stock. In the conclusion, the average performance of selected dam lines O and T strains were superior to the imported parents stock in the over all results of this experiment. A comparison of relative performance between selected superior female breeders and Arkansas meat performance egg phase test, there were no significant difference in terms of average performance in livability, egg weight, conversion of feed into eggs, sexual maturity and adult body weight. The broiler test represents the performance of the progeny from the matings between selected superior female lines and certain selected male lines. The average performance of selected certain broiler lines were about the same performance as the imported broiler strains and there was no significant differences between average performance selected domestic broiler lines and Arkansas meat performance test.

國産鷄 改良을 위한 合成種 育種에 關한 硏究

BONG KUG OHH(吳鳳國) 한국육종학회 1979 한국육종학회지 Vol.11 No.2

This experiment was based on single cross data during 64 weeks from diallel crossing system to identify superior cross combinations in Seoul National University, College of Agriculture, Poultry Breeding Farm. Total 1599 birds of 10 single strain crosses were obtained from 4 inbred lines of white Leghorn, A(domestic), S(domestic), C(imported), and K(imported). CK crossbred, crossproduct of C and K purebreds which were selected for resistent to Limphoid Leuicosis in U.S.A., showed the most losses due to Leukosis. Therefore this study seems to be concluded that the lowest viability results from interaction between genes for Leukosis and Korean environment. In estimate of combining abiliy, egg productivities of A and K strains were identified as superior for general combining ability, while combining ability of S strain which showed the best performance among 4 purebreds is very low and in this result it was evident that performance of crossbred was not dependent upon that of it’s parent but combining ability between parents. Since combining ability variance for egg weight of all strains is very low compared with error variance, improvement of this character in use of cross combinations of these experimental strains will not be expected. In breeding for body weight, considering heavier layer requires more feed for body maintenance, A and K strains calculated lower combining ability variance were desirable. Following the above results, using the A and K strains among 4 experimental strains in this study were agreed to be able to improve the laying productivity through their cross combination for their superior combining ability.

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.

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.

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.

난용종계의 란중증대성과 기지 형질의 유전력 및 상관관계에 관한 연구

한성욱,오봉국 ( Seung W . Han,Bong Kug Ohh ) 한국축산학회 1975 한국축산학회지 Vol.17 No.1

The present study was conducted to estimate the heritabilities and genetic correlations. among the egg weight increase in pullet year and certain other economic traits of egg production stocks and to obtain information useful for the genetic improvement of Korean laying stocks especially for the improvement of egg weight. The data used in this study were the records on 3,121 White Leghorn hens from three different strains, LD, LH ana DS which were raised from 1964 to 1968 at Han Hyup Poultry Breeding Farm in Seoul. The traits studied were average weight of first ten eggs, average egg weight to 400 days of age, average March egg weight, body weight at 8 weeks of age, number of eggs. to 300 days of age, number of eggs to 400 days of age, age at first egg, age at average egg weight, time interval from first egg to average egg weight, and winter pause. The results obtained are as follows. 1. In the averages of each traits computed for each strain, the average weight of first ten eggs was 42.5±5.2g for the DS strain, 42.4±4.8g for the LD strain, and 43.9±5.4g for the LH strain, respectively; the average egg weight to 400 days of age and that in March were 50.3 and 53.9g for the DS strain, 51.3 and 54.5g for the LB strain, and 52.7 and 55.8g for the LH strain; body weights at 8 weeks for the DS, LD and LH strains were 580.2, 595.6 and 606.3g, respectively; numbers of eggs to 300 and 400 days of age were 72 and 138 for the DS strain, 72 and 141 for the LD strain, and 65 and 132 for the LH strain; age at first egg was 179 days for the DS strain, 181 days for the LD strain, and 186 days for the LH strain, respectively; age at average egg weight in pullet year was 260 days for the DS strain, 261 days for the LD strain, and 265 days for the LH strain; time intervals from first egg to average egg weight were 81 days for the DS strain, 73 days for the LD strain, and 79 days fer the LH strain. The range of winter pause for the three strains was 13∼23 days. 2. The range of heritability estimates derived from the sire component of variance in the three strains were 0.20∼0.45 for average weight of first ten eggs, 0.15∼0.89 for March egg weight, 0.15∼0.66 for egg weight at 400 days of age, 0.24∼0.64 for body weight at 8 weeks, 0.10∼0.14 for number of eggs to 300 days, 0.09∼0.21 for number of eggs to 400 days, 0.13∼0.44 for age at first egg, -0.11∼0.10 for age at average egg weight, 0.14∼0.18 for time interval from first egg to average egg weight, and -0.07∼0.00 for winter pause. The heritabilities of age at average egg weight were very low and those of time interval from first egg to average egg weight were of intermediate value, suggesting that the latter trait would be more useful for the improvement of egg weight increase than age at average egg weight. 3. Positive values of maternal variance were estimated in all three strains for number of eggs to 300 days of age, number of eggs to 400 days of age, age at average egg weight, and for winter pause, although the magnitude of them were somewhat different depending on the strain. For egg weight, the maternal variance was consistantly recognized only in the DS strain. 4. The genetic correlation of average weight of first 10 eggs with number of eggs to 300 and 400 days of age was -0.48∼-0.59 and -0.39∼-0.76, respectively. The genetic correlation of the trait with average egg weights to 400 days of age and with average March egg weight was 0.23∼0.93 and 0.44∼0.85, respectively. The correlations between average of first 10 eggs and 8 weeks body weight were generally positive, but were very low. The genetic and phenotypic correlations of age at first egg with number of eggs to 300 days of age were -0.48∼-0.84. The phenotypic correlations of age at first egg with number of eggs to 400 days were negative and high. But there were considerable differences between the strains in the genetic correlations of the trait with number of eggs to 400 days of age. The genetic correlation