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This study was conducted to construct basic data for the selection of elite cows by analyzing the estimated breeding value (EBV) and accuracy using the pedigree of Hanwoo cows in Gyeongnam. The phenotype trait used in the analysis are the carcass weight (CWT), eye muscle area (EMA), backfat thickness (BFT) and marbling score (MS). The pedigree of the test group and reference group was collected to build a pedigree structure and a numeric relationship matrix (NRM). The EBV, genetic parameters and accuracy were estimated by applying NRM to the best linear unbiased prediction (BLUP) multiple-trait animal model of the BLUPF90 program. Looking at the pedigree structure of the test group, there were a total of 2,371 cows born between 2003 to 2009, of these 603 cows had basic registration (25%), 562 cows had pedigree registration (24%) and 1,206 cows had advanced registration (51%). The proportion of pedigree registered cows was relatively low but it gradually increased and reached a point of 20,847 cows (68%) between 2010 to 2017. Looking at the change in the EBV, the CWT improved from 4.992 kg to 9.885 kg, the EMA from 0.970 cm2 to 2.466 cm2, the BFT from −0.186 mm to −0.357 mm, and the MS from 0.328 to 0.559 points. As a result of genetic parameter estimation, the heritability of CWT, EMA, BFT, and MS were 0.587, 0.416, 0.476, and 0.571, respectively, and the accuracy of those were estimated to be 0.559, 0.551, 0.554, and 0.558, respectively. Selection of superior genetic breed and efficient improvement could be possible if cow ability verification is implemented by using the accurate pedigree of each individual in the farms.

Pusan National Univ(Department of Animal Science), Pusan 609-735, KoreaABSTRACTThe present study data were obtained from 36,894 cows in Korea Animal Improvement Association from 2001 to 2009 which was subjected for ultrasound measurements(eye muscle area, back-fat thickness, marbling score) and descent. Repeated record models were carried out using 7,913 of 36,894 of total animal traits. The ultrasound measured traits and performance test data were used to study the chest girth, body condition score, eye muscle area, back-fat thickness and marbling score with genetic correlation and parameters for the ultrasound measured traits using REMLF90 program. Genetic correlation of eye muscle area with back-fat thickness, marbling score and back-fat thickness with marbling score were noticed in repeated records animal model as 0.69, 0.54, and 0.59, whereas in multiple trait animal model method were 0.07, 0.66, and 0.39, respectively. Repeated records of animal models were used as positive correlation of traits. Multiple trait animal models were used as negative correlation of eye muscle area with marbling score. The analysis on repeat records of animal models using ultrasound measurements about Korean cattle showed positive effects for each traits. In comparison differences between the repeat records of animal models and multiple trait animal models was found with higher traits of her, the heritability and repeatability was found higher in repeat records animal models. In light of these assessments, carcass traits by ultrasound measurements are expected to help and improve an accurate analysis of each trait and if the research analysis using repeat records of animal models continue when we estimate genetic ability of these traits. (Key words : Carcass trait, Repeated records animal model, Ultrasound)

This study was carried out to investigate the correlation of body measurement type and carcass traits. This study used body measurement type and carcass traits on 1,312 heads of Hanwoo steers tested(24 months) which was from 1997 to 2002 at Hanwoo Improvement Main Center National Agricultural Cooperatives Federation. Body measurement type used the age of 18 months body measurement type, and carcass traits used the results of decision grade of Animal Products Grading Service. Observing the phenotypic correlation between carcass traits and body measurement type from the result, the weight, withers height, and chest width at age of 18 months and carcass weight showed readings of 0.690, 0.483, and 0.506, respectively. Also, eye muscle area and age of 18 months weight and chest width read 0.356 and 0.279, respectively. According to results, that improvements in weight, withers height, and chest width are likely to enlarge the eye muscle area and meat production level. Not only quality improvement but also quantity augmentation affect income and sales of the farmers. As can be seen in this study, improvements of weight, withers height and chest width should always be put to much effort while other body measurement type should be considered continuously too. In order to attain clearer results further studies should be done on body measurement type, which will contribute to the improvements of body measurement type in Hanwoo.

This study aims to estimate the genetic parameters for carcass traits on Hanwoo of breeding farmhouses using Animal Products Grading Service’s data of 428,812 cattle from 101 slaughterhouses nationwide from 2000 to 2005. Using carcass traits of carcass weight, eye muscle area, backfat thickness, marbling score, meat color and fat color that greatly influence Hanwoo's grade, the effects of carcass year, carcass season, sex and carcass region were estimated.Based upon carcass traits of carcass weight, eye muscle area, backfat thickness, marbling score and meat color that greatly influence Hanwoo’s grade, the heritabilities and genetic parameters were estimated of 17,578 Hanwoo slaughtered in 2005 with existing herdbook, where EM-REML algorithm was used in estimating genetic parameters.The mean and standard deviation of each carcass trait are 321.42±53.62 kg, 76.25±10.43cm 2 , 9.96± 4.14mm, 3.75±2.00, 4.83±0.48 and 2.99±0.40, for carcass weight, eye muscle area, backfat thickness, marbling score, meat color and fat color, respectively.As a result of analysis on the effects of carcass year, the carcass weight, backfat thickness and meat color came out highest as 359.40±0.181, 9.82±0.017 and 4.90±0.002, respectively in 2004. As a result of analysis on the effects of carcass season, the carcass weight and eye muscle area came out highest as 345.88±0.144 and 79.57±0.033 respectively in spring, and the backfat thickness was highest as 8.78±0.013 in winter, and the meat color and fat color slightly came out higher as 4.88±0.002 and 2.96±0.001 in fall, while the marbling score was highest as 3.29±0.006 in summer. The results of the analysis on the effects of sex indicated that the backfat thickness and fat color were highest as 10.53±0.010 and 3.07±0.001 in cow, the carcass weight came out highest in Hanwoo steer as 368.03±0.068 kg, the eye muscle area were highest as 82.96±0.042 in bull, and the marbling score was highest as 4.19±0.007 in steer, and the meat color was highest as 4.89±0.001 in cow.Regarding the results of analysis on the effects of carcass region, the carcass weight, eye muscle area