Article

Development of nutrigenomic based precision management model for Hanwoo steers

Chandima Gajaweera1, Dong Hun Kang2, Doo Ho Lee3, Yeung Kuk Kim3, Bo Hye Park2, Seung Hwan Lee3,*, Ki Yong Chung2,**
Author Information & Copyright
1Department of Animal Science, Faculty of Agriculture, University of Ruhuna, Matara Matara, Sri Lanka.
2Department of Livestock Science, Korea National University of Agriculture and Fisheries, Jeonju 54874, Korea.
3Division of Animal and Dairy Science, Chungnam National University, Daejeon 34134, Korea.
*Corresponding Author: Seung Hwan Lee, Division of Animal and Dairy Science, Chungnam National University, Daejeon 34134, Korea, Republic of. E-mail: slee46@cnu.ac.kr.
**Corresponding Author: Ki Yong Chung, Department of Livestock Science, Korea National University of Agriculture and Fisheries, Jeonju 54874, Korea, Republic of. E-mail: cky95@korea.kr.

© Copyright 2023 Korean Society of Animal Science and Technology. This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Focusing high marble deposition, Hanwoo feedlot system uses high-energy diet over the prolonged fattening period. However, due to the individual genetic variation, around 40% of them are graded into inferior quality grades (QG), despite they utilized the same resources. Therefore, focusing to develop a nutrigenomic based precision management model, this study was to evaluate the response to the divergent selection on genetic merit for marbling score (MS), under different dietary TDN (total digestible nutrient) levels. Total of 111 calves were genotyped and initially grouped for estimated breeding value (high and low) for marbling score (MS-EBV). Subsequently, managed under two levels of feed TDN%, over the calf period, early, middle, and final fattening periods following 2 x 2 factorial arrangement. Carcasses were evaluated for MS, Back fat thickness (BFT) and Korean beef quality grading standard. As the direct response to the selection was significant, the results confirmed the importance of initial genetic grouping of Hanwoo steers for MS-EBV. However, dietary TDN level did not show an effect (p>0.05) on the MS. Further, no genetic-by-nutrition interaction for MS (p>0.05) was also observed. The present results showed no correlation response on BFT (p>0.05), indicating that the selection based on MS-EBV can be used to enhance the MS without undesirable effect on BFT. Ultimate turnover of the Hanwoo feedlot operation is primarily determined by the QGs. The present model shows that the initial grouping for MS-EBV increased the proportion of carcasses graded for higher QGs (QG1++ and QG1+) by approximately 20%. Moreover, there appear to be a potential to increase the proportion of QG 1++ animals among the high-genetic group by further increasing the dietary energy content. Overall, this precision management strategy suggests the importance of adopting an MS based initial genetic grouping system for Hanwoo steers with a subsequent divergent management based on dietary energy level.

Keywords: Precision; management; marbling; Hanwoo