Untargeted metabolomics confirms the association between plasma branched chain amino acids and residual feed intake in beef heifers

Abstract

This study explored plasma biomarkers and metabolic pathways underlying feed efficiency measured as residual feed intake (RFI) in Charolais heifers. A total of 48 RFI extreme individuals (High-RFI, n = 24; Low-RFI, n = 24) were selected from a population of 142 heifers for classical plasma metabolite and hormone quantification and plasma metabolomic profiling through untargeted LC-MS. Most efficient heifers (Low-RFI) had greater (P = 0.03) plasma concentrations of IGF-1 and tended to have (P = 0.06) a lower back fat depth compared to least efficient heifers. However, no changes were noted (P ≥ 0.10) for plasma concentrations of glucose, insulin, non-esterified fatty acids, β-hydroxybutyrate and urea. The plasma metabolomic dataset comprised 3,457 ions with none significantly differing between RFI classes after false discovery rate correction (FDR > 0.10). Among the 101 ions having a raw P < 0.05 for the RFI effect, 13 were putatively annotated by using internal databases and 6 compounds were further confirmed with standards. Metabolic pathway analysis from these 6 confirmed compounds revealed that the branched chain amino acid metabolism was significantly (FDR < 0.05) impacted by the RFI classes. Our results confirmed for the first time in beef heifers previous findings obtained in male beef cattle and pointing to changes in branched-chain amino acids metabolism along with that of body composition as biological mechanisms related to RFI. Further studies are warranted to ascertain whether there is a cause-and-effect relationship between these mechanisms and RFI.

Effects of rumen-bypass protein supplement on growth performance, hepatic mitochondrial protein complexes, and hepatic immune gene expression of beef steers with divergent residual feed intake

“…For instance, Elolimy et al [10], observed a connection between RFI and protein turnover and transport mechanisms in rumen epithelium of beef cattle. Our recent study by Taiwo et al [11] and those of others [12–14] have further illuminated the link between RFI and amino acid metabolism in beef cattle. The results of these studies invariably highlight amino acid metabolism as one of the pathways associated with RFI phenotype in beef cattle, implying significant disparities in nitrogen utilization efficiency among beef cattle based on RFI variations.…”

Some plasma biomarkers of residual feed intake in beef cattle remain consistent regardless of intake level

“…Group B-Restricted (0-70 days) www.nature.com/scientificreports/ branched-chain amino acids, decreased in efficient compared to inefficient RFI heifers 15 . Likewise, studies in pigs have also linked plasma α-aminoadipic acid levels and the lysine degradation pathway to the RFI phenotype 26 .…”

“…The plasma concentration of IGF-1 has been shown to correlate with RFI in various cattle studies 15,36 . However, diet-dependent relationships were highlighted in a review of the literature 4 , with a negative relationship, such as the one found in the present study, consistently observed only with low-concentrate and low-energy diets.…”

“…However, whether these metabolic regulations play a causal role or are merely associated with RFI due to covariance with feed intake remains uncertain. For instance, multiple studies have suggested that the plasma concentration of branchedchain amino acids, having signalling roles in key metabolic pathways such as protein and lipid synthesis, could serve as potential biomarkers of RFI in beef cattle 11,[14][15][16][17] . Likewise, a meta-analysis of genome-wide association studies conducted on beef cattle concluded that the only metabolic pathway genetically linked to RFI was the…”

Effects of Dietary Protein Levels on Sheep Gut Metabolite Profiles during the Lactating Stage

“…Dietary protein optimization based on metabolomic insights can lead to precise feeding for sustainable livestock production as varying dietary protein levels can lead to changes in metabolite profiles and metabolic pathways. It is established that dietary protein levels have an influence on amino-acid metabolism leading to changes in the concentrations of blood-circulating amino acids and related metabolic pathways in cattle [ 15 ]. Keeping in mind the intertwined metabolism of protein with energy, we assumed that changes in dietary protein contents may cause alterations in the concentrations of those metabolites that are involved in energy production, storage, and utilization.…”