돼지에 있어 복당산자수와 복당포유개시자돈수의 유전력과 유전상관

정흥우,박영일 ( H . W . Chung,Y . I . Park ) 한국축산학회 1986 한국축산학회지 Vol.28 No.9

Data from 351 purebred Large White litters produced by 34 sires were utilized to obtain genetic and phenotypic parameter estimates for the total number of pigs born per litter, the number of pigs born alive per litter and the number of pigs suckled per litter. The heritabilities and genetic and phenotypic correlations were estimated from the sire components of variance and covariance. Heritabilities estimated in this study were 0.10±0.20 for the total number of pigs born per litter, 0.14±0.20 for the number of pigs born alive per litter .and 0.08±0.20 for the number of pigs suckled per litter. The genetic correlations of the total number of pigs born per litter with the number of pigs born alive per litter and the number of pigs suckled per litter were 1.18 and 0.75 respectively, and the genetic correlation between the number of pigs born alive per litter and the number of pigs suckled per litter was 0.83. Phenotypic correlations among the litter traits were highly positive.

모돈의 자돈 생산성에 영향을 미치는 요인 분석

정흥우,( H . W . Chung,L . Wang,M . F . Rothschild ) 한국축산학회 1998 한국축산학회지 Vol.40 No.1

Records from 16,351 litters born between 1991 and 1996 from Duroc, Landrace and Yorkshire sows and Landrace × Yorkshire crossbred sows were used to estimate the effects of year, parity and breed on eight sow productive traits at birth. The model used in this study included effects of year, parity, breed, sow nested within breed, and the interactions of year by parity and parity by breed. The results obtained were as follows: Year had highly significant effects (P$lt;0.01) on the numbers of stillbirths, pigs mummified, small pigs, and pigs suckled and litter weight. The breeds of sow significantly affected (P$lt;0.01) the total number of pigs born, the number of stillbirths, small pigs, pigs culled, and pigs suckled and litter weight. The total number of pigs born, the number of pigs suckled and litter weight were the highest in the 4th parity. The number of stillbirths, pigs mummified and small pigs tended to inaease with the inaease of parity. Parity effects were significant on most of the traits. The total number of pigs born and the number of pigs suckled were greater in the crossbred sows than in the purebreds (P$lt;0.01) and litter weight was heavier in the crossbred sows than in the purebreds (P$lt;0.05). In purebreds, Landrace and Yorkshire sows were superior to Duroc sows in the total number of pigs born and the number of pigs suckled (P$lt;0.01). Landrace Yorkshire crossbred sows were similar to Yorkshire Landrace crossbreed in the sow productive traits. Heterosis were 9.3% for the total number of pigs, 11.6% for the number of pigs suckled, 4.3% for litter weight, 25.0% for the number of stillbirth, 23.1% for the number of pigs mummified and 20.0% for the number of pigs culled.

돼지에 있어 성장율 , 등지방두께 , 체장 및 체고에 대한 유전모수의 추정

정흥우(H . W . Chung),박영일(Y . I . Park) 한국축산학회 1990 한국축산학회지 Vol.32 No.5

This study was conducted to estimate the heritabilities and genetic and phenotypic correlations among average daily gain, age at 90kg, backfat thickness, body length and wither`s height. The data used for this study were obtained from 5,386 heads of Duroc, Landrace and Yorkshire boars and gifts tested on a weightconstant basis at S Swine Breeding Farm at Icheon, Kyunggi Do from August, 1982 to August, 1987. The results obtained in this study are summarized as follows ; 1. The heritabilities of the traits estimated by sire variance component were 0.259±0.081 for average daily gain, 0.288±0.082 for age at 90kg, 0.409±0.100 for backfat thickness, 0.160±0.064 for body length and 0.201±0.062 for wither`s height, respectively. 2. The genetic correlations of average daily gain with age at 90kg, backfat thickness, body length and wither`s height were -0.765, -0.084, -0.202 and -0.081, respectively. The genetic correlations of age at 90kg with backfat thickness, body length and wither`s height were 0.127, 0.203 and 0.045 respectively. The genetic correlations of backfat thickness with body length and wither`s height were -0.202 and -0.216, respectively and the genetic correlation between body length and wither`s height was 0.334. 3. The phenotypic correlations of average daily gain with age at 90kg, backfat thickness, body length and wither`s height were -0.771, -0.102, -0.048 and-0.032, respectively. The phenotypic correlations of age at 90kg with backfat thickness, body length and wither`s height were 0.133, 0.037 and 0.033.. respectively. The phenotypic correlations of backfat thickness with body length and wither`s height were -0.144 and 0.158, respectively and the estimate of body length with wither`s height was 0.293 in phenotypic correlation.

돼지에 있어 등지방두께에 대한 종모돈 평가에 관한 연구

정흥우(H . W . Chung),박영일(Y . I . Park) 한국축산학회 1990 한국축산학회지 Vol.32 No.12

This study was conducted to estimate the breeding value of sire for backfat thickness in swine by BLUP and least squares method, to estimate the correlations among the breeding values estimated by the two methods and to compare the efficiency of the two methods of estimating the breeding value. The data used in this study were obtained from 5,386 heads of Durocs, Landraces and Yorkshires tested on a weight-constant basis at S. Swine Breeding Farm in Icheon, Kyunggi-Do from August, 1982 to August, 1987. The results obtained in this study are summarized as follows. 1. The correlation between the breeding values of sire estimated by the BLUP and least squares method in male offspring was 0.778 and 0.799, respectively, in Durocs and Yorkshires, and the correlation in female offspring was 0.974 and 0.817, respectively, in the two breeds. These correlations were highly significant. 2. The correlations between the breeding value of sire estimated by the male offspring and the breeding value of the same sire estimated by the female offspring were higher in the BLUP than in the least squares estimates. 3. The BLUP appears to be more efficient than the least squares method in estimating the breeding value in view of the magnitude of the standard errors. 4. Although the BLUP is more efficient than the least squares method in estimating the breeding value, the least squares method may be used for the estimation of breeding value, if G^-1-value is not known correctly or if it is difficult to use the BLUP, in view of the positive and high correlations between the breeding values estimated by the two methods.

돼지의 성장율과 등지방 두께에 대한 유전 및 환경요인의 효과

정흥우(H . W . Chung),박영일(Y . I . Park) 한국축산학회 1989 한국축산학회지 Vol.31 No.9

The purpose of this study was to investigate the effect of sex, breed, year of birth, month of birth, parity of sows and litter size on average daily gain, age at 90kg and backfat thickness in swine. The data used in this study were obtained from 7,650 heads of Duroc, Hampshire. Landrace and Yorkshire boars and gilts tested on an age-constant basis at a swine breeding farm in Chungchongbuk-Do from March, 1984 to February, 1987. The results obtained in this study are summarized as follows: l. The least-squares overall means of the traits studied were. 0.780±0.003kg for average daily gain, 155.6±0.3 days for age at 90kg and 1.679±0.008cm for backfat thickness. respectively. 2. Males had significantly higher average daily gain and earlier age at 90kg and thinner backfat than females. 3. Among the breeds compared, the Duroc had the highest average daily gain and reached 90kg at the earliest age. The Hampshire had the thinnest backfat. 4. Year of birth and month of birth affected the three traits studied significantly. The pigs born in June and July had comparatively higher average daily gain and reached 90kg at an earlier age than those born in other months. The pigs born in March and April had lower average daily gain, and the pigs born in December and January had the thinnest backfat. 5. The effect of litter size was statistically significant for none of the three traits studied. 6. The pigs in 2nd parity had the highest average daily gain and reached 90kg at the earliest age. Backfat was thinnest in the 3rd parity.

돼지에 있어 일당증체량과 등지방두께에 대한 선발지수

권오섭,김성훈,정흥우,박영일 ( O . S . Kwon,S . H . Kim,H . W . Chung,Y . I . Park ) 한국축산학회 1986 한국축산학회지 Vol.28 No.10

Selection index for average daily gain and backfat thickness was derived from the genetic and phenotypic parameters estimated on the basis of the data from 3,369 heads of Yorkshires, Durocs, Hampshires and Landraces tested from March, 1984 to August, 1985. The results obtained in this study are summarized as follows; 1. The heritabilities of average daily gain estimated were 0.369, 0.470, 0.318 and 0.367, respectively, in Yorkshires, Durocs, Hampshires and Landraces and the average heritability was 0.381. The heritabilities of backfat thickness estimated were 0.404, 0.662, 0.565 and 0.892, respectively, in Yorkshires, Durocs, Hampshires and Landraces and the average heritability was 0.631. 2. The genetic correlations between average daily gain and backfat thickness were 0.238, 0.425, -0.132 and 0.079, respectively, in Yorkshires, Durocs, Hampshires and Landraces and the average genetic correlation was 0.152. The phenotypic correlations between average daily gain and backfat thickness, were 0.147, 0.321, 0.020 and 0.147, respectively, in Yorkshires, Durocs, Hampshires and Landraces and the average phenotypic correlation was 0.159. 3. The selection index derived from the estimated parameters and economic weights based on the data from market survey on the price of the products was I₁= =X₁+ 6.52X₂ and the index from the economic weights based on the regression analysis of the price of the breeding stocks was I₂= =X₁+ 2.94X₂. (X₁= backfat thickness(㎝), X₂=average daily gain(㎏))

순종과 교잡종 돼지의 복당 산자수와 21일령 체중에 근거한 종모돈의 평가

배규한(G . H . Bae),정흥우(H . W . Chung),서강석(K . S . Seo),박영일(Y . I . Park) 한국축산학회 1994 한국축산학회지 Vol.36 No.1

The breeding values of the Landrace boars were estimated bused on the records of the purehred Landrace and the crossbred between Landrace and Large Yorkshire by best linear unbiased prediction(BLUP) and least squares methods for litter size and 21-day weight to study the relationship between the breeding values estimated by the performances of purebreds and crossbreds. The data used in this study were the records of 3.170 litter of the Landrace purebreds and the crossbreds between Landraces and Large Yorkshires farrowed at the J. Swim Breeding Fann in Jeonnam Province from January. 1984 to December. 1991. The correlation between the breeding value, of the boars estimated on the basis of the purebred and crossbred performances by the BLUP was 0.253 for the litter size and 0.801 for 21-day weight. The correlation between the breeding values of the boars estimated on the basis, of the purebred and crossbred performances by the lest squares method was 0.712 fir the litter size arid 0.853 for 21-day weight.

돼지의 복당산자수와 생시체중에 미치는 교배조합의 효과

김종복(J . B . Kim),정흥우(H . W . Chung),박영일(Y . I . Park) 한국축산학회 1988 한국축산학회지 Vol.30 No.8

This study was conducted to study the effect of mating types on the total number of pigs born per litter, number of pigs suckled per litter and birth weight of pigs. The data for this study were obtained from 32,821 litters of the Yorkshire, Landrace, Hampshire and Duroc purebreds and the crossbreds which were produced by crossing the Yorkshire, Landrace, Hampshire, Duroc and Spot and farrowed from Jan., 1979 to June, 1985. The data were statistically analysed by the least-squares method. The results obtained in this study are as. follow s. 1. The least-squares overall means were 9.99±0.04 for the total number of pigs born per litter, 9.33±0.04 for the number of pigs suckled per litter and 1.38±0.04Kg for the birth weight of pigs. 2. Among the purebreds, the Landrace had the largest number of pigs born and suckled per litter, followed in rank by Yorkshires, Durocs and Hampshires. The Duroc was the heaviest in the birth weight of pigs, followed in rank by Hampshires, Landraces and Yorkshires. 3. The backcrosses, 3-breed crosses and the two multiple crosses produced by 3-breed cross dams had larger number of pigs born and larger number of pigs suckled pet litter than the purebreds or two breed crosses due to the maternal heterosis. The 3-breed crosses and the multiple crosses by 3-breed cross dams tended to have heavier birth weight than the 2-breed crosses. 4. The total number of pigs born per litter, number of pigs suckled and birth weight of the first parity sows were inferior to those of the second parity sows. The number born and number suckled per litter of the 4th and 5th parity sows were larger than those of other parity sows and the birth weights of the second and 3rd parity sows were heavier than those of other parity sows. 5. The sows furrowed in May, June and September tended to have larger number of pigs born and suckled compared with those furrowed in other months of the year and the birth weight of pigs furrowed in the spring was heavier than those furrowed im the summer.

돼지에 있어 복당산자수와 복당체중의 유전력과 유전상관

김종복(J . B . Kim),정흥우(H . W . Chung),박영일(Y . I . Park) 한국축산학회 1988 한국축산학회지 Vol.30 No.10

Heritabilities and correlations between litter size and litter weight at birth and at weaning were estimated from paternal half-sib analyses on the basis of the data from 2,156 litters of purebred Landraces, Yorkshires, Durocs and Hampshires. The results obtained in this study are summarized as follows; 1. Heritabilities of litter size at birth and at weaning estimated were 0.20 ±0.09 and 0.11 ±0.08 for Landraces, 0.25 ± 0.12 and 0.14 ± 0.11 for Yorkshires, 0.04 ± 0.09 and 0.03 ± 0.09 for Durocs, and 0.12 ± 0.10 and 0.10 ± 0.10 for Hampshires, respectively. Heritability estimates of litter weight at birth and at weaning were 0.32 ± 0.11 and 0.11 ± 0.08 for Landraces, 0.32 ± 0.13 and 0.12 ± 0.10 for Yorkshires, 0.23 ± 0.13 and 0.08 ±0.10 for Durocs, and 0.09 ±0.10 and 0.03 ±0.08 for Hampshires, respectively. 2. The genetic correlations of litter size at birth with litter size at weaning and litter weight at weaning were 0.82 and 0.56 for Landraces, 0.76 and 0.49 for Yorkshires, 0.53 and 0.47 for Durocs 0.79, and 0.33 for Hampshires, respectively. The genetic correlations between litter size at weaning and litter weight at weaning were 0.92 for Landraces, 0.83 for Yorkshires, 0.74 for Durocs, and 0.73 for Hampshires, respectively. 3. The phenotypic correlations of litter size at birth with litter size at weaning and litter weight at weaning were 0.78 and 0.70 for Landraces, 0.75 and 0.65 for Yorkshires, 0.80 and 0.73 for Durocs, and 0.83 and 0.73 for Hampshires, respectively. The phenotypic correlations between litter size at weaning and litter weight at weaning were 0.88 for Landraces, 0.88 for Yorkshires, 0.91 for Durocs, and 0.91 for Hampshires, respectively

젖소에 있어서 성장호르몬 ( BST ) 투여가 산유량 , 혈청내 BST 농도 및 우유내 BST 농도에 미치는 영향

권관(K . Kwon),정흥우(H . W . Chung),주종철(J . C . Joo) 한국축산학회 1991 한국축산학회지 Vol.33 No.10

This study was carried out to investigate the effect of BST treatment on milk production. and BST concentration in serum and milk of Holstein cows. The data used in this study were obtained in 9 Holstein cows. The results obtained in this study are summarized as follows ; 1. Milk yield of BST group was higher by 8.6% than that of controls. 2. Least-squares means of milk yield significantly differed between BST group and controls from 2 to 15 days after BST treatment(p$lt;0.05). but did not differ after 16 days. 3. Serum BST concentration of BST group was significantly higher than that of controls until 8 days after teatment(p$lt;0.05). but was not higher after 12 days. 4. BST concentration in milk did not significantly differ between BST group and controls.