Progress of the Southern Multi-Breed Resource Population: Hard-to-measure phenotypes to drive genomic selection

This paper describes the progress in the first half of a large, 5-year breeding project run across New South Wales involving five temperate beef breeds and the Brahman breed. The project's purpose is to generate up to 8,000 progeny that allows the benefits of genomic selection to be captured, particularly for traits that are lowly recorded due to being difficult or costly to record or which are yet to be routinely included in genetic evaluations, e.g., fertility, health, and resilience. The project has generated 4,886 progeny from three cohorts, with another 1,990 females to calve in mid-2023. Cohort one, born in 2020, has now had all steers complete feedlot finishing with carcass traits recorded, with the heifers having completed their first calving and subsequent rebreed. Details concerning the recording of hard-to-measure traits to this point in the project are provided. The high-density SNP genotypes collected, and the recording of these traits will contribute to the genomic reference populations and BREEDPLAN evaluations of the breeds involved.