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.

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.

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.

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.

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 Ⅲ. 交雜種과 純種間의 比較

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

This experiment was carried out to identify the differences of genetic materials as genetic marker for crossbred of egg type and dual purpose chicken. The characteristics of chromosomes in egg type and dual purpose hybrid were as follows. The differences from the origin of the parent chromosomes were found that chromosome #2-q was non-banded centromere, #4-q was dark band adjacent to centromere as the marker of meat type chick, and Z chramosome was faint dark band adjacent to centromere.

肉用種鷄의 育種開發을 위한 交雜試驗 : I. Selection of Superior Stock in Female Line Ⅰ.母系統 優良 交配 組合 選拔試驗

吳鳳國,呂政秀 서울大學校 農科大學 1977 서울대농학연구지 Vol.2 No.1

A Study on crossbreeding of Broiler Production in Poultry This study was carried out to improve broiler production and to estimate a genetic value and to select superior broiler breeder stock by means of crossbreeding under domestic feeding and management conditions. 1. Selection of superior stock in females. The data used in this study were the rocords of two selected superior breeder stocks, one strain of domestic superior broiler parent stock and added one strain of imported parent stock. A total of 1,020 chicks of parent stock were used in this experiment. The results obtained in this study are summarzed as follows; (1) The average viability of brooding period was 95.20% and the highest viability was A strain (98.85%), and lowest viability was D strain. There was significant difference between A and D strains. The death of the chicks was due mainly to paralysis and catarrh of crop. (2) The average viability of growing period was no singificant difference between experimental strains. (3) With respect to the laying hen viability, the average viability was 92.71%and the highest viabllity was 96.55% in C strain, and the lowest viability were 91% in A and D strains. The death of the laying hens was due mainly to Lymphoid Leukosis Complex in D strain, (4) The average body weight at 6 weeks of age was 953g and the highest body weight was 986g in D strain, and the lowest body weight was C strain (936g). The D strain was superior to the other strains in the body weight at 6 weeks of age and there was significant difference between D and others strains. (5) The average feed conversion at 6 weeks of age was 2.11kg and the highest feed effeciency was A strain (2.06kg). The A strain was improved feed efficiency about 0.1kg compared with D strains. (6) The growth rate of growing period was normally developed comparing with breeder pullet mean body weight and feed recommendations. There was no significant difference between experimental strains. (7) The average body weight at 24weeks of age was 2,775g and this body weight was slightly overweighed compared with recommended feeding standard, however there was no signifiicant difference between strains. (8) The average adult body weight at 58 weeks of age was 3,356g and highest body weight was 3,416g in D strain, and the lowest body weight was 3,296g in A strain. The adult body weight of laying period was normally maintained compared with breeder pullet feeding recommend-ations. (9) The average date of sexual maturity was 179days and the earlist sexual maturity was 176days in D strain and the latest sexual maturity was 183 days in C strain. (10) The average hen-day egg production from 24 to 58 weeks of age was 62% and the high-est egg production strain was A strain (66%), and the lowest egg production was D strain (60%). The A strain was about 6% higher than the imported parent stock (D strain). The hen-housed average egg production was 145 eggs and the A strain had about 11 egg higher egg production than the D strain. In statistical analysis for egg production, there was significant difference between A strain and the other strains. (11) In egg weight, the average egg weight was 61g and the highest egg weight was D strain-(62.7g) and the lowest egg weight strain was A strain (60g). It seems to be important to improve egg weight in domestic strains. (12) The average conversion of feed into egg production was 219.8g and the lowest feed requirement strain was A strain(206.6g), and the highest feed requirement strain was C strain(227.3g). It seems to be important in economic point and A strain was superior to the imported parent stock (D strain). (13) In economic analysis of broiler breeder stock, the average net income per layer was 2,661 won and the highest net income was A strain (2,919won) and the lowest net income was imported parent stock (2,402won). With respect to the cost of per egg production, the average egg production cost was 29 won and the lowest production cost was A strain(27.52won). Egg production cost of D strain which was imported broiler breeder stick was 30.29won and the D strain needed more cost 2.77won to produce per egg compared with the A strain. (14) Average fertility of selected superior stock in female lihe was 98.3% and the lowest fertility was B strain (97.9%). The average of hatchability was 93.8% and the highest hatchability was (B ×Y) crossbreds (96.3%) and the lowest hatchability was(B ×X) crossbred(93.6%) and imported parent stock (90.2%).