우량육용계의 선발을 위한 교잡시험

박영일,백동훈 ( Y . I . Park,D . H . Baik ) 한국축산학회 1973 한국축산학회지 Vol.15 No.4

The purpose of this experiment was to compare the performance of the crosses of seven different stocks to Cornish males for broiler production. The seven stocks used as female parents were White Plymouth Rocks, Columbians, Barred Plymouth Rocks, New Hampshires, Stock D, Stock C, and Stock H. The first four stocks, WR, Columbian, BR, and NH were the pure Strains that had been maintained at the College of Agriculture, Seoul National University. The Stock D was the female parent stock of a broiler stock produced by a Korean Poultry Breeding Farm. The stocks C and D were the commercial chicken of two different broiler stocks imported from abroad. The commercial chicks of the imported Hubbard Broilers were used as the control to compare with the seven different crosses mentioned above. The average body weight at 8 weeks of age was 1,596 grams for the Hubbard Broilers, 1,563 grams for the C×Cornish, and 1,544 grams for the H×Cornish, all of which were significantly larger than those of other stocks compared. The income per bird over the cost of feed and day-old chick was largest for the C×Cornish, followed in rank by the H×Cornish, Hubbard Broilers, D×Cornish, Columbian×Cornish, NH×Cornish, BR×Cornish, and WR×Cornish. The superior performance of the C×Cornish and H×Cornish appeared to be due to the effect of the genes transmitted from their dams. The hens of the Stock C had a higher rate of laying, and had a heavier egg weight than those of the Stock H. The age at 50% production was 196 days for the Stock C, 195 days for the Stock H and 179 days for the Stock D. The average body weight of the hens at 30 weeks of age was about 3.2㎏ for both Stocks C and H.

돼지에 있어 산자수 , 동복자생시체중 및 임신기간의 유전력 , 반복력 및 유전상관

백동훈,박영일,오봉국,한성욱 ( D . H . Baik,Y . I . Park,B . K . Ohh,S . W . Han ) 한국축산학회 1974 한국축산학회지 Vol.16 No.2

The heritabilities, repeatabilities, and genetic correlations among litter size, litter weight at birth and gestation length were estimated on the basis of the data obtained from 614 litters (5,547 pigs) of the Landrace raised at the St. Isidore Farm over a 3-year period from the spring of 1969 to the winter of 1971. The effects of the year and season of birth and parity were estimated by the least square method. These estimates were used for the statistical adjustment of the data for the differences in certain environmental factors. The heritabilities and genetic correlations among the traits studied were estimated from the sire components of variance and covariance. The repeatahilities were estimated from the intra-class correlation among repeated measurements of the traits for the same dam. The results obtained are as follows. 1. The estimates of beritabilities were 0.097±0.061 for the total number of pigs born, 0.204±0.107 for the gestation length, 0.124±0.090 for the number of pigs born alive and 0.059±0.065 for the litter weight at birth. 2. The estimates of repeatabilities were 0.136±0.102 for the total number of pigs born, 0.779±0.034 for the gestation length, 0.129±0.099 for the number of pigs born alive, and 0.091±0.148 for the litter weight at birth. 3. The phenotypic correlation of the total number of pigs horn was 0.037 with the gestation length. 0.932 with the number of pigs born alive, and 0.766 with the litter weight ai birth. The phenotypic correlation of the gestation length was 0.175 with the number of pigs born alive and 0.266 with the litter weight at birth. The phenotypic correlation between tile number of pigs born alive and the litter weight at birth was 0.812. 4. The genetic correlation of the total number of pigs born was 0.188 with the gestation length, 0.955 with the number of pigs born alive, and 0.839 with the litter weight at birth. The genetic correlation of the gestation length was 0.128 with the number of pigs born alive and 0.059 with the later weight at birth. The genetic correlation between the number of pigs born alive and the litter weight at birth was 0.940.

한우의 경제형질에 관한 연구 1 . 출생년도 및 계절의 영향

백동훈,신원집,나승환,정연후 ( D . H . Baik,W . J . Shin,S . H . Na,Y . H . Chung ) 한국축산학회 1985 한국축산학회지 Vol.27 No.7

Data obtained from the total of 683 calves (351 males and 332 females) were analyzed to study differences in economically important traits of Korean native cattle among years and seasons of birth. The calves were born in the Alpine Experiment Station from 1970 to 1983 and reared to 24 months of age for the progeny test of their sires. Average weights were 24.5, 86.7, 117.0, 239.6 and 320.7 ㎏ at birth, 4, 6, 12 and 18 months of age, respectively. Year of birth was an important source of variation for all of the traits studied. The body weights were getting heavier as the year of birth elapsed except for the years 1977, 1978 and 1979. Digestible CP and TDN were varying over the years. Season of birth was a significant source of variation for the weights at birth and 4 months of age but for the weights at 6, 12 and 18 months of age, it failed to show significance. Calves born in fall had lightest weights at all of the age periods classified in this study. The CP and TDN consumption showed to have higher in spring and winter born calves.

실험동물의 생산성에 대한 잡종강세 1 . 생쥐의 생산기간에 따른 생산효율

백동훈(D . H . Baik),나종삼(J . S . Na),최호성(H . S . Choi) 한국축산학회 1990 한국축산학회지 Vol.32 No.4

To observe effectiveness of the various crossing systems on the productivity in mice, the weights of products and efficiency of production which were composed of weights of all of the progeny at weaning and weight gain of both parents over the fifth parity were analyzed. Heterosis percentages computed on the weights of products ranged from 1.9% to 9.9% in the single crosses and from 25.4% to 33.7% in the back crosses, while those on the efficiency of production were in between 2.4-9.5%, 20.3-27.6% and 13.0-24.1%, respectively for the single, back and 3 way crosses. To find out the effectiveness of crossing between lines of mice as a model for livestock crossbreeding, calculation of production efficiency was attempted over the 5th parity.

교잡종 번식우에 있어서 초산일령과 (初産日齡) 생산효율에 미치는 종모우의 (種牡牛) 품종 및 사료중 에너지수준의 영향

백동훈 ( D . H . Baik ) 한국축산학회 1984 한국축산학회지 Vol.26 No.1

Four groups of crossbred cows (14 Hereford x Holstein, 14 Angus x Holstein, 15 Simmental x Holstein and 11 Chianina x Holstein) were maintained on two levels of nutrition (high TDN and low TDN) until they produced two weaned calves. The cows started to be bred at their first estrus to Jersey bulls and rebred at first estrous cycles following the first calving to Charolais bulls. Efficiency of production was examined in two ways; 1) Ratio of the weaning weight of calf to the TDN consumed by cow during prepartum and preweaning periods and by calf for preweaning period (El). 2) Ratio of the weaning weight of calf plus weight assessment of cow (5/8 cow weight) to the TDN consumption by cow and by calf for the same duration as in the E1 computation (E2). The ages at first calving were in the order of Hereford, Angus, Simmental and Chianina crossbred cows from the youngest to the oldest. High energy ration group calved six months earlier than low ration group. The difference in the age at first calving was largest between Hereford and Chianina crossbred cows (693 vs. 776 days). Smaller sized cows (Hereford and Angus crossbreds) reached puberty and calving earlier and consumed less TDN, which resulted in being more efficient than larger sized breeding groups. When culled cow weight is included in the product term, the efficiency of production (E2) seemed to be more dependent on the age at first calving for the large sized cows on low ration as judged by the correlation coefficients.

HCCI에 적용하기 위한 EGR이 PRF70/공기 혼합기의 점화지연에 미치는 영향

백동훈(D. H. Baik),이수룡(S. R. Lee) 대한기계학회 2018 대한기계학회 춘추학술대회 Vol.2018 No.12

The effects of EGR on ignition delay of PRF70/air mixture was numerically investigated with detailed chemical reaction mechanism. The Chemkin-III was utilized to evaluate the delay time of autoignition for isobaric conditions and simulate the HCCI engine conditions. For water vapour adding, the dilution and thermal effects cause the ignition delay to increase, while the chemical effect makes the ignition delay shortened. The ignition delay by the chemical effect is reduced by the increase of fuel oxidation rate. In the case of CO₂ addition, the higher value of specific heat of CO₂ makes thermal effect more important. The addition of CO₂ does not affect the quantity of radicals like H, O, and OH, which results in the reduction of chemical effect. In HCCI engine, adding EGR gas makes pressure rise rates decreased. As a result, the load range can be prolonged and even in higher load PRR remains acceptable. The dilution and thermal effects are more important than the chemical effect.

실험동물의 생산성에 대한 잡종강세 2 . 산자수에 대한 어미의 유전자형과 교배조합의 효과

백동훈(D . H . Baik),나종삼(J . S . Na),최호성(H . S . Choi) 한국축산학회 1991 한국축산학회지 Vol.33 No.3

To investigate the effects of genotypes of dam and type of mating of parents on the litter sizes at birth and weaning, the dta collected from 3lines of mice and their crosses were analyzed. Maternal heterosic effects on the litter size were high in the crosses involving highly inbred C₃H line. The percent heterosis on the litter size was generally higher at weaning than at the time of birth which implies crossbred clams raise their pups better than straightbred dams. Back crosses exerted higher heterosis when the dams were younger (at early parity), while the 3-way crosses showed higher at older ages especially for the litter size at weaning.

돼지의 주요 경제형질에 대한 환경요인의 영향

백동훈(D . H . Baik),최호성(H . S . Choi),송주엽(J . Y . Song),손삼규(S . K . Son),오하식(H . S . Oh) 한국축산학회 1995 한국축산학회지 Vol.37 No.6

To investigate the genetic and environmental effects on the economically important traits in swine, data on 4.782 pigs tested from 1990 through 1993 at a test station were analysed. The statistical model applied for the analysis was consisted of sex, breed, purity, year and season of birth as main effects with the interaction of the year×season. Males bowed greater duly gain by about 50g, thiner backfat, and reached 90㎏ body weight earlier than females. By computing with the game index, the males showed greater values than females. Duroc showed faster growth, and thicker backfot, while Yorkshire was superior in feed conversion to the other two breeds. The backfat thickness was smaller in the pigs of 2nd parity, but the clays to reach 90㎏ body weight tends to be shorter in the pigs of 3rd parity. The pig bom in toll or winter grew faster than those born in spring or summer season. The year effect on most of the traits showed gradual progress representing the results of the selection and/or replacement effects by the parent stock imported from many foreign countries over a long, period.

돼지에 있어서 품종 , 산차 및 분만계절이 산자수에 미치는 효과

백동훈(D . H . Baik),나승환(S . H . Na),신원집(W . J . Shin) 전북대학교 농업과학기술연구소 1983 농업생명과학연구 Vol.14 No.-

한우의 체위측정치에 (體位測定値) 대한 임신단계 및 제요인의 효과

최호성,백동훈,신원집,손주엽,나중삼 ( H . S . Choi,D . H . Baik,W . J . Shin,J . Y . Song,C . S . Na ) 한국축산학회 1996 한국축산학회지 Vol.38 No.1