요크셔 종빈돈의 검정성적에 영향하는 환경요인 추정

This study was carry out to study on the on-farm performance test and the birth records of 9,086 gilts of Yorkshire purebred obtained from 2000 to 2010 in KAYA GGP. The effects of year of birth, season of birth, year of final test, season of final test, final test day on major economic traits such as days age at 90 kg, average daily gain, backfat thickness, eye muscle area and lean percent were analyzed. Regression and phenotypic correlation coefficients analyses were made to estimate the effects of economic traits on final test day. The results obtained from this study were summarized as follows; The means for each trait were 147.537 ± 12.401 days for age at 90 kg, 614.614 ± 56.900 g for average daily gain, 15.771 ± 3.071 mm for backfat thickness, 28.644 ± 3.634 cm2 for eye muscle area, 55.363 ± 3.901% for lean percent. Season of birth affected significantly backfat thickness, eye muscle area and lean percent. The backfat thickness was thinnest in summer by showing 15.385 ± 0.085 mm. Backfat thickness was thickest 16.361 ± 0.079 mm in winter. The eye muscle area, lean percent were highest in spring by showing 29.759 ± 0.091 cm2 and 56.221 ± 0.099%, respectively. As the year of birth passed, backfat thickness and days at 90 kg showed decreased. The performances of the fall test seasons showed significantly superior to other seasons by showing in days age at 90 kg and average daily gain. summer test season showed poor to other season. backfat thickness was thickness in fall Phenotypic correlation coefficients between all traits were significantly different. Significant negative phenotypic correlation coefficients were found between days to 90 and average daily gain, positive phenotypic correlation coefficients were found between days to 90 and backfat thickness, negative phenotypic correlation coefficients were found between average daily gain and backfat thickness. negative phenotypic correlation coefficients were found between backfat thickness and eye muscle area(-0294), backfat thickness and lean percent(-0.723), positive phenotypic correlation coefficients were found between eye muscle area and lean percent(0.586) Based on the results of regression coefficients analyses for the effects of economic traits on final test day, the estimated equation coefficients were -0.04 mm in backfat thickness, 0.02 cm2 in eye muscle area, and 0.03% in lean percent , -1.26 g in average daily gain, 0.61 days in days to 90 kg. Especially average daily gain, days to 90kg were found that affected economic traits. From the results described above, a simple conclusion that the final test day effect showed significant for all traits, and it could be considerable in terms of on-farm performance test in major economic traits. However, there could be various effects influencing economic traits, further research is needed to find out whether the effect is genetic or environmental.