Article

Parameter Estimation and Assessment of Bias in Genetic Evaluation of Carcass Traits in Hanwoo Cattle Using Real and Simulated Data

Mohammed Bedhane1,*, Julius van der Werf2, Sara de las Heras-Saldana2,3, Leland Ackerson IV1, Dajeong Lim4, Byoungho Park4, Mi Na Park4, Seung Roh5, Samuel Clark2
Author Information & Copyright
1College of Agriculture & Natural Resources, Michigan State University, East Lansing 48824, United States.
2School of Environmental and Rural Science, University of New England, Armidale 2351, Australia.
3AGBU, a joint venture of NSW Department of Primary Industries and University of New England, Armidale 2351, Australia.
4National Institute of Animal Science, RDA, Jeollabuk-do 55365,, Korea.
5Hanwoo Genetic Improvement Center, NAGI, Jeollabuk-do 55365, Korea.
*Corresponding Author: Mohammed Bedhane, College of Agriculture & Natural Resources, Michigan State University, East Lansing 48824, United States. E-mail: benegash@gmail.com.

© 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

Most carcass and meat quality traits are moderate to highly heritable, indicating that they can be improved through selection. Genetic evaluation for these types of traits is performed using performance data obtained from commercial and progeny testing evaluation. The performance data from commercial farms are available in large volume, however, some drawbacks have been observed. The drawback of the commercial data is mainly due to sorting of animals based on live weight prior to slaughter, and this could lead to bias in the genetic evaluation of later measured traits such as carcass traits. The current study has two components to address the drawback of the commercial data. The first component of the study aimed to estimate genetic parameters for carcass and meat quality traits in Korean Hanwoo cattle using a large sample size of industry-based carcass performance records (n=469,002). The second component of the study aimed to describe the impact of sorting animals into different contemporary groups based on an early measured trait and then examine the effect on the genetic evaluation of subsequently measured traits. To demonstrate our objectives, we used real performance data to estimate genetic parameters and simulated data was used to assess the bias in genetic evaluation. The results of our first study showed that commercial data obtained from slaughterhouses is a potential source of carcass performance data and useful for genetic evaluation of carcass traits to improve beef cattle performance. However, we observed some harvesting effect which leads to bias in genetic evaluation of carcass traits. This is mainly due to the selection of animal based on their body weight before arrival to slaughterhouse. Overall, the non-random allocation of animals into a contemporary group leads to a biased estimated breeding value in genetic evaluation, the severity of which increases when the evaluation traits are highly correlated.

Keywords: bias; carcass traits; heritability; harvesting effect; genetic evaluation; commercial data