Expression of candidate genes for residual feed intake in beef cattle

Abstract

Residual feed intake (RFI) has been adopted in Australia to measure feed efficiency in cattle. RFI is the difference between the observed feed intake by an animal and its predicted feed intake based on its size and growth rate over a test period. Gene expression profiling of 8 candidate genes (AHSG, GHR, GSTM1, INHBA, PCDH19, S100A10, SERPINI2 and SOD3) was conducted using liver samples from steers from the Angus Society Elite Progeny Test Program following an RFI test. In addition expression of these genes was studied on animals in an experiment consisting of two breeds (Angus and Brahman), two sexes (heifer and steer) and HGP treatment vs. no treatment. Our results show that GSTM1 was highly expressed in steers phenotypically ranked high for RFI in the Angus Elite Sire Progeny Test and that HGP treatment also had an effect on expression of this gene. No significant differences in expression were detected between breeds and only AHSG was differentially expressed between sexes.