On the value of adding commercial data into the reference population of the Angus SteerSELECT genomic tool

Abstract

Context Angus SteerSELECT is a genomic tool designed to provide genomic estimated breeding values (GEBV) for nine traits related to growth, feedlot performance, carcase characteristics and immune competence. At present, GEBV for carcase characteristics are based on a reference population of 3766 Australian Angus steers. Aims We aimed to investigate the potential benefit of incorporating commercial data into the existing reference population of the Angus SteerSELECT. To this aim, we employ a population of 2124 genotyped commercial Angus steers with carcase performance data from four commercial feedlot operators. Methods The benefit of incorporating the commercial data (COMM) into the reference (REFE) population was assessed in terms of quality and integrity of the COMM data and meta-data to model the phenotypes adequately. We computed bias, dispersion, and accuracy of GEBV for carcase weight (CWT) and marbling (MARB) before and after including the COMM data, in whole or in partial, into the REFE population. Key results The genomic estimate of the Angus content in the COMM population averaged 96.9% and ranged from 32.87% to 100%. For CWT, the estimates of heritability were 0.419 ± 0.026 and 0.368 ± 0.038 for the REFE and COMM populations respectively, and with a genetic correlation of 0.756 ± 0.068. For MARB, the same three parameter estimates were 0.357 ± 0.027, 0.340 ± 0.038 and 0.879 ± 0.073 respectively. The ACC of CWT GEBV increased significantly (P < 0.0001) from 0.475 when the COMM population was not part of the REFE to 0.546 (or 15%) when a random 50% of the COMM population was included in the REFE. Similarly significant increases in ACC were observed for MARB GEBV (0.470–0.521 or 11%). Conclusions The strong genomic relationship between the REFE and the COMM populations, coupled with the significant increases in GEBV accuracies, demonstrated the potential benefits of including the COMM population into the reference population of a future improved version of the Angus SteerSELECT genomic tool. Implications Commercial feedlot operators finishing animals with a strong Angus breed component will benefit from having their data represented in the reference population of the Angus SteerSELECT genomic tool.

Wagyu Feeder Check: A genomic-based tool to identify performance differences of Australian Wagyu and Wagyu crossed cattle

“…Unlike the recent work of Reverter et al (2023) with 3766 purebred Angus steers plus 2124 Angus-based commercial steers, in the present study we did not observe a tendency for over-dispersion (or inflation) of GEBV for CWT or MARB. Similarly, the recent work by Koo et al (2023) exploring the quality of the genomic evaluation of Korean Hanwoo cattle based on a large number of genotyped cows, steers and young animals applied the LR method to confirm a slight negative bias (GEBV overestimation) for all traits and animal groups, but a slight positive bias (GEBV underestimation) for CEMA and MARB in steers.…”

“…The former has been validated using historical data from 153 978 registered Angus animals; the latter has been validated using a population of 522 short-fed (100 days) or long-fed (270 days) Angus steers finished in commercial feedlots. Also, for SteerSELECT the potential benefit of incorporating commercial data in the reference population has been evaluated (Reverter et al 2023).…”

“…for FADG, CWT, and CEMA of 1.59 ± 0.33 kg/day, 432.99 ± 65.60 kg and 90.06 ± 10.86 cm 2 , respectively. More recently,Reverter et al (2023) with a population of 2120 Angus-based steers from four commercial feedlots feed for an average of 222.46 day, reported means ± s.d. for CWT and MARB of 425.45 ± 43.94 kg and 3.64 ± 1.33, respectively.…”