Effects of Genetic and Environmental Factors on Ultrasonic Estimates of Carcass Traits of Japanese Brown Cows |
T. D. Sri Rachma Aprilita Bugiwati, H. Harada, R. Fukuhara |
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Abstract |
A study was made of the effects of genetic and environmental factors on ultrasonic estimates of carcass traits of Japanese Brown cows. The M. longissimes thoracis area (MLTA), Subcutaneous (SFT) and Inter Muscular (IMFT) Fat Thickness, Rib Thickness (RT) and Beef Marbling Score (BMS) were scanned at the 7th rib by ultrasound. Significant differences between sires, raising place, birth year and season were found for all traits. The heritabilities estimates for sire or Maternal Grand Sire (MGS) on ultrasonic estimates of carcass traits ranged from 0.05~0.14. Genetic and phenotypic correlations among the ultrasonic estimates were positive (0.13~0.88 and 0.24~0.75). Raising place effects were significant for all traits and the differences were between 30.8~33.5 cm2 for MLTA and 0.46~0.67 for BMS. Cows born in 1988 tended to have high MLTA, SFT, IMFT and RT but low BMS. Cows born in spring tended to have high MLTA. Cows born in winter or autumn tended to have high BMS. The interaction effects of birth year with birth season were significant for both MLTA and BMS. |
Keywords:
Japanese Brown Cow; Ultrasonic Estimates; Carcass traits; Genetic Parameters |
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