Accounting for herd movement characteristics in carcase trait genetic evaluations of commercial beef cattle

Implications Accounting for herd movement by fitting variables as random effects was more appropriate considering the unstructured nature of the commercially derived beef carcase trait dataset.

Introduction Carcase traits, measured on commercial animals processed in abattoirs, have the potential to be useful for genetic improvement programs. The data have the characteristics of being measured late in life and collected in high volume at a low cost. However, unlike the pedigree performance recording system, animals are not treated alike as commercial animals can frequently be moved between different herd locations. Previous genetic evaluation studies have recognised the unstructured nature of commercially derived data, but lacked a unified approach as to how to account for herd movement (Hickey et al. 2007; Pabiou et al. 2011). The aim of this study was to determine an appropriate method to account for herd movement for the purposes of genetic evaluation of abattoir carcase data.