• Journal of Animal Science and Technology
• /
• v.55 no.1
• /
• pp.7-11
• /
• 2013

The purpose of this study was to estimate (co) variance components of three milk production traits for genetic evaluation using a multiple lactation model. Each of the first five lactations was treated as different traits. For the parameter estimation study, a data set was set up including lactations from cows calved from 2001 to 2009. The total number of raw lactation records in first to fifth parities reached 1,416,589. At least 10 cows were required for each contemporary group, herd-year-season effect. Sires with fewer than 10 daughters were discarded. Lactations with 305d milk yield exceeding 15,000 kg were removed. In total, 1,456 sires of cows were remained after all the selection steps. A complete pedigree consisting of 292,382 records was used for the study. A sire model containing herd-year-season, caving age, and sire additive genetic effects was applied to the selected lactation data and pedigree for estimating (co) variance components via VCE. Heritabilities and genetic or residual correlations were then derived from the (co) variance estimates using R package. Genetic correlations between lactations ranged from 0.76 to 0.98 for milk yield, 0.79~1.00 for fat yield, 0.75~1.00 for protein yield. On individual lactation basis, relatively low heritability values were obtained 0.14~0.23, 0.13~0.20 and 0.14~0.19 for milk, fat, and protein yields, respectively. For the combined lactation heritability values were 0.29, 0.28, and 0.26 for milk, fat, and protein yields. The estimated parameters will be used in national genetic evaluations for production traits.

• Journal of Korean Society of Forest Science
• /
• v.58 no.1
• /
• pp.27-33
• /
• 1982

Genetic variance and heritability for height growth of Populus alba${\times}$ P. glandulosa were estimated. Remarkable different between P. alba${\times}$ alba(Italy), female and P. alba naturalized in Korea was observed in the genetic variance and therefore genetic character of the P. alba${\times}$ alba(Italy) was considered better than that of P. alba. The heritability (83%) for the female was considerably high. On the other hand, P. glandulosa, pollen tree. showed narrow genetic variance and also very heritability(17%). Two(A and B) of three pollen trees showed the same trend in the genetric variance. However, the other(c) was somewhat different from A and B. Similarly, rooting ability of cuttings differed between female trees, but did not between male trees. Naturalized Pl alba showed relatively higher rooting ability than P. alba${\times}$ alba(Italy). In the pollen trees, the ability was similar in two male trees. However, the other male tree(c) was slightly poorer than the other two.

• Journal of agriculture & life science
• /
• v.44 no.6
• /
• pp.83-89
• /
• 2010

The objective of this study was to investigate the effect of the environmental and genetic factors on the carcass traits of Korean cattle. We have used the data of 22,954 Korean cattle slaughtered from 2005 to 2009 in Gyeongnam region and estimated the genetic parameters of 36,868 cattle including the pedigree individuals by means of EM-REML analytical method. In summary, the heritability of the carcass weight, eye muscle area, backfat thickness and marbling score was 0.39, 0.30, 0.33 and 0.62, respectively. The carcass weight and the eye muscle area showed high correlation between them with the genetic correlation of 0.86 and the phenotypic correlation of 0.72. The high heritability of marbling score is assumed to be the result of focusing the breed improvement on the quality of the meat. Through this study, it is considered that the Korean cattle in Gyeongnam region are improving, which will thus contribute to the increase of the farmer's income. Additional study on the economic trait must be carried out to obtain clearer results that will lead to further improvement of Korean cattle.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.11
• /
• pp.350-356
• /
• 2017

This study was conducted to examine the influence of the maternal genetic effect of swine on their economic traits through the estimation of their genetic parameters, breeding value and genetic trends using an animal model. The data on Duroc pigs, Korean Native Pigs and Synthetic pigs (Duroc ${\times}$ Korean Native Pig) from 2000 to 2015 were obtained from the National Institute of Animal Science in Korea and used to estimate the genetic parameters for the average daily gain (ADG) and backfat thickness (BFT). Model 1 included the additive genetic effect of the animals, Model 2 consisted of Model 1 + the maternal genetic effect and Model 3 consisted of Model 2 + the maternal permanent environment effect. The heritability calculated by estimating the additive genetic effect was higher than that calculated by estimating the maternal genetic effect using the maternal animal model. The estimated genetic correlations between the additive and maternal genetic effects for the ADG and BF were strongly negative. Thus, the estimation of the breeding value can be used to select the most appropriate individuals and make an optimal breeding scheme.

• The Korean Journal of Malacology
• /
• v.29 no.4
• /
• pp.325-334
• /
• 2013

The purpose of this paper is to compare and analyze family variations for growth-related traits of Pacific abalone, Haliotis discus hannai. Genetic parameters and breeding values were estimated using all measurement data like shell length, shell width, and total weight as 18-month-old growth traits of 5,334 individuals of selected third generation's Pacific abalone produced in 2011. Family variations of 865 individuals of the upper 10 families with the largest number were inspected. Overall mean in phenotypic traits of 18-month-old Pacific abalone which was investigated in this study showed 54.5 mm of shell length, 36.8 mm of shell width and 21.3 g of total weight respectively. And, variation coefficient of total weight was 51.0%, so variability of data was shown to be higher than 21.1% of shell length and 20.7% of shell width. The family effects showed significant difference by each family (p < 0.05), and heritability of shell length, shell width, and total weight was medium with 0.370, 0.382, and 0.367 respectively. So it is considered that family selection is more advantageous than individual selection. On the basis of breeding values of estimated shell length and total weight, to investigate distribution and ranking by each individual about the upper 10 families with the largest number of individuals, the values were used by being changed into standardized breeding values. Based on shell length, it was investigated that the individual number of the upper 5.4% is 152 and the number of the lower 5.4% is 8. In case of total weight, it was inspected that the individual number of the upper 5.4% is 164 and the number of the lower 5.4% is 1. Like these, phenotypic and genetic diverse variations between families could be checked. By estimating genetic parameters and breeding values of a population for production of the next generation, if they are used properly in selection and mating, it is considered that more breeding effects can be expected.

• Korean Journal of Poultry Science
• /
• v.47 no.4
• /
• pp.267-274
• /
• 2020

This study was conducted to estimate genetic parameters for growth and egg production traits in Black Korean native chicken (L strain) and Korean White Leghorn (F, K strains) using a multi-traits animal model BLUP. Traits used for this study were body weight at 150 days (BW150) and 270 days (BW270), age at first egg (DAY1st), egg weight at first egg (EW1st) and 270 days (EW270), and number of eggs laid by 270 days (EP270), and included 68,688 pedigree and 123,905 performance records collected from 2001 to 2013. In L, F, K strains, heritability estimates of BW150 were high (0.48, 0.52 and 0.50, respectively); of BW270 were high (0.56, 0.57 and 0.56); of DAY1st were medium to high (0.45, 0.39 and 0.31); of EW1st were low (0.15, 0.16 and 0.15); of EW270 were high (0.58, 0.55 and 0.59) and of EP270 were moderate (0.22, 0.21 and 0.20). The genetic and phenotypic correlation of DAY1st with EP270 were highly negative (-0.73 to -0.63 and -0.48 to -0.42). The genetic and phenotypic correlation of EP270 with BW150 and BW270, respectively were low negative (-0.16 to 0.01 and -0.14 to -0.03) and low to moderate positive (-0.08 to 0.07 and -0.13 to 0.04). The genetic and phenotypic correlation of EW270 with BW150 and BW270, respectively were moderate to high positive (0.39 to 0.49 and 0.36 to 0.46) and (0.29 to 0.33 and 0.34 to 0.37). The study showed that there is a potential for genetic improvement of Korean Indigenous chicken through selection program.

• Journal of Animal Science and Technology
• /
• v.53 no.2
• /
• pp.99-106
• /
• 2011

This study estimated the genetic parameters of growth-related traits from 11-month-old olive flounder (Paralichthys olivaceus) base population in which wild and cultured broodstocks were introduced. The heritability of body weight, total length, body height, body shape, and condition factor of the base population was estimated to be 0.754, 0.753, 0.789, 0.438, and 0.369, respectively. Genetic correlations between body weight and total length, between body weight and body height, and between total length and body height were 0.969, 0.960, and 0.960, respectively, showing highly positive correlation. Genetic correlations between body weight and body shape, between total length and body shape, between body height and body shape were -0.403, -0.344, and -0593, respectively, showing low negative correlation. Overall, olive flounder might be an appropriate selective breeding species with the high heritability of the traits in an 11-month-old population.

• Journal of Animal Science and Technology
• /
• v.54 no.1
• /
• pp.9-14
• /
• 2012

The purpose of this study was to estimate heritabilities and genetic correlations for reproductive and productive traits and to apply their estimates to selection strategies in a swine population. Reproductive and productive traits considered in this study were number of born alive piglet (NBA), number of weaned piglet (NW), loin eye area (LEA), days to 90 kg (D90KG), back fat thickness (BF), and lean meat content (LEAN). Data were collected from 9,886 litters on 2,447 sows for reproductive traits and 10,181 gilts and boars for productive traits from Jan. 2000 to Dec. 2008 in a swine GGP farm. The statistical model to estimate genetic parameters for considering traits was a multiple traits animal model with including animal and maternal additive effects and litter effects on reproductive traits and animal additive effects on productive traits as random as well as some of fixed effects. For estimating (co) variance components of several random effects, restricted maximum likelihood methodology was used on this assumed model. The estimated heritabilities by animal additive effects and maternal effects were 0.07 and 0.02 for NBA and 0.03 and 0.02 for NW, respectively. Genetic correlation estimate for direct genetic effects between NBA and NW was 0.14. Heritability estimates for direct genetic effects were 0.19, 0.39, 0.36, and 0.43 for LEA, D90KG, BF and LEAN, respectively. The genetic correlation of LEA with LEAN was 0.35. Productive traits were antagonistically correlated with reproductive traits. From these results it is concluded that, if selection is done for strong positive effects of reproductive traits, then this would decline productive performance.

• Korean Journal of Poultry Science
• /
• v.17 no.4
• /
• pp.243-254
• /
• 1990

This study was carried out to investigate the effectiveness of the selection for commercial populations of layer chickens subjected to multiple objectives. For that purpose, predicted selection responses obtained from estimated genetic parameters and observed values were compared. Data for two layer pure lines, Line-w(Single Comb White Leghorn) and Line-B (brown layer) which have been maintained at the Mani Breeding Farm were collected from 1980 to 1985 during 5 generations. The annual genetic gains were estimated by the moth of selection index in retrospect on the basis of selection differentials, phenotypic and genetic variance-covariance for the traits considered. SM was found to be shorten by 1.67 days and 1.14 days per generation in Line-W and Line-B. EN300 and EN400 were found to be increased by 4.15 and 5.92 per generation in Line-W and 257 and 3.73 per generation in Line-B. The annual gains realized were found to be significantly different from expected gains predicted on the basis of the annual selection differentials and genetic parameters in later generations, but it could not be concluded that the differences were attributed to genetic effects.

• Journal of agriculture & life science
• /
• v.51 no.4
• /
• pp.111-119
• /
• 2017

The objective of this study is to check the applicability of the improved trait through the nutritional value of loin and the estimation of genetic parameter through the chemical composition analysis(moisture, crude fat, crude protein, crude ash) for Hanwoo carcass traits and loin. The data of 1kg of loin sampled and analyzed for 2,033 Hanwoo progeny test(steers) from $47^{th}$ to $57^{th}$ were used as the disclosure material used in this study. The study resulted that the heritability for carcass weight, eye muscle area, back fat thickness and marbling score which are Hanwoo carcass traits was estimated to be 0.37, 0.51, 0.44 and 0.57, respectively and the heritability for moisture, crude fat, crude protein and crude ash which are the chemical composition analysis to be 0.62, 0.64, 0.58 and 0.12, respectively. And the genetic correlation estimate between carcass weight and crude fat was 0.35, and marbling score with moisture, crude fat, crude protein and crude ash was -0.966, 0.964, -0.924 and -0.664, respectively. The genetic correlation between moisture and crude fat, crude protein was analyzed to be -0.998, 0.969 and a high genetic correlation was shown in crude fat and crude protein, -0.979. As the chemical composition analysis value showed high heritability in moisture, crude fat and crude protein, improved traits are considered to be available.