Figure 1.
Figure 1.

The mRNA expression of neuropeptides, (A) neuropeptide-Y (NPY), (B) agouti-related protein (AGRP), (C) Pro-opiomelanocortin (POMC), and (D) relaxin-3 (RLN3) in the arcuate nucleus of steers identified as low Residual Feed Intake (RFI) or high RFI. Expression was determined by real-time RT-PCR. Values were normalized to eukaryotic translation initiation factor 3 subunit K (EIF3K) expression. Data are expressed as fold change relative to High RFI steers and calculated according to Pfaffl (2010). Bars denoted by * differ (P < 0.05), Low, n = 8, High, n = 6.

 


Figure 2.
Figure 2.

The mRNA expression of neuropeptide receptors, (A) melanocortin 3 receptor (MC3R), (B) melanocortin 4 receptor (MC4R), and (C) relaxin/insulin-like family peptide receptor 1 (RXFP1) in the arcuate nucleus of steers identified as either low Residual Feed Intake (RFI) or high RFI. Expression was determined by real-time RT-PCR. Values were normalized to eukaryotic translation initiation factor 3 subunit K (EIF3K) expression. Data are expressed as fold change relative to High RFI steers and calculated according to Pfaffl (2010). Bars denoted by * differ (P < 0.05), Low, n = 8, High, n = 6.

 


Figure 3.
Figure 3.

The hypothalamic expression of (A) gonadotropin releasing hormone (GnRH) and (B) gonadotropin inhibiting hormone (GnIH) mRNA and pituitary expression of (C) follicle stimulating hormone β polypeptide (FSHβ) and (D) luteinizing hormone β polypeptide (LHβ) mRNA in steers identified as either low Residual Feed Intake (RFI) or high RFI. Expression was determined by real-time RT-PCR. Values were normalized to eukaryotic translation initiation factor 3 subunit K (EIF3K) expression. Data are expressed as fold change relative to High RFI steers and calculated according to Pfaffl (2010). Bars denoted by * differ (P < 0.05), Low, n = 8, High, n = 6.

 


Figure 4.
Figure 4.

The adipose tissue expression of leptin mRNA in steers identified as either low Residual Feed Intake (RFI) or high RFI. Expression was determined by real-time RT-PCR. Values were normalized to eukaryotic translation initiation factor 3 subunit K (EIF3K) expression. Data are expressed as fold change relative to High RFI steers and calculated according to Pfaffl (2010). Bars denoted by * differ (P < 0.05), Low, n = 8, High, n = 6.