Detection of a Gene Affecting Body Weight of Hanwoo Cattle in Korea

Detection of a Gene Affecting Body Weight of Hanwoo Cattle in Korea The Hanwoo breed of beef cattle is considered one of Korea’s most important native livestock resources. The animals have a yellow-brown to tan color and a relatively small body size, with an adult size of just over 500 kg (see photo). Although the breed historically played a major role in providing draft for rice production, they have been largely raised for production of beef since the late 1960’s. The meat of the Hanwoo is considered by Koreans to be of exceptional quality and thus commands a price several times higher than that from exotic species. This factor has contributed to maintenance of a stable population of the breed. In addition, the country maintains a very active programme in breed improvement, to help ensure the advantages of the Hanwoo over outside breeds. This programme is largely the responsibility of the National Livestock Research Institute in Suwon, a contributor to the RAS5044 project. These activities include conventional breeding and progeny test programmes, as well as the application and experimentation with more futuristic technologies such as marker assisted selection and animal cloning. A recent study has examined effects of a particular gene, Stearoyl-CoA Desaturase (SCD) on body weight in the Hanwoo.

Detection of a Gene Affecting Body Weight of Hanwoo Cattle in Korea Four genetic evaluation models were applied to investigate the effect of SCD. All four models included year-season group as a fixed effect and age of days in slaughter as a covariate term. The models differed with respect to the effect of the SCD polymorphism. The first model did not consider SCD, while models 2, 3, and 4 assumed additive, dominance, and recessive inheritance patterns, respectively. Models were compared using likelihood ratio test (LRT). The results of LRT showed that the models 3 and 4 were superior to model 1 for the analysis of live weight and that model 4 provided the best fit for carcass weight. These results thus indicated a significant (P < 0.05) effect of the SCD polymorphism on the body weight of Hanwoo with non-additive inheritance patterns. Current work is evaluating the usefulness of considering SCD genotypes in the Hanwoo selection programme.

Source: Yong-Min Cho*, National Livestock Research Institute, RDA, Suwon, Korea. variance@rda.go.kr

* Dr. Yong-Min Cho was a participant in the regional training course on Selection Breeding and Gene Technologies, held in association with regional TC project RAS5044.