Author
Lindholm-Perry, Amanda | |
BUTLER, ASHLEY - North Carolina State University | |
Kern, Rebecca | |
HILL, R - University Of South Florida | |
Kuehn, Larry | |
Wells, James - Jim | |
Oliver, William | |
Hales Paxton, Kristin | |
Foote, Andrew | |
Freetly, Harvey |
Submitted to: Animal Genetics
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/29/2016 Publication Date: 7/18/2016 Publication URL: http://handle.nal.usda.gov/10113/62858 Citation: Lindholm-Perry, A.K., Butler, A.R., Kern, R.J., Hill, R., Kuehn, L.A., Wells, J., Oliver, W.T., Hales, K.E., Foote, A.P., Freetly, H.C. 2016. Differential gene expression in the duodenum, jejunum and ileum among crossbred beef steers with divergent gain and feed intake phenotypes. Animal Genetics. 47(4):408-427. doi: 10.1111/age.12440. Interpretive Summary: Characteristics of the small intestine like mass and cellularity have previously been associated with cattle feed efficiency. The small intestine in cattle is responsible for enzymatic digestion of nutrients and absorption of fatty acids, amino acids and sugars and contributes to the overall feed efficiency of cattle. As such, the objective of this study was to evaluate the expression of over 24,000 genes in the three sections of the small intestine to determine whether differences were associated with gain and feed intake in beef steers. Gene expression analyses were performed comparing high gain versus low gain animals, high intake versus low intake animals, and comparing each of the four gain x intake groups to each of the others. Gene groups differentially expressed within the most efficient and least efficient groups of animals included those involved in immune function, inflammation and transcription. The high gain-high intake group differed from other groups by immune response genes and ribosomal genes. The animals with low gain-low intake displayed greater abundance of stress response genes compared to all other groups of animals. Several metabolic and cellular pathways were identified as important for gain and/or intake. These included antigen processing/presentation pathway in high versus low gain animals and fatty acid, glucose, starch/sucrose metabolism and the retinol metabolism pathway in the high versus low intake animals. In summary, we have identified genes with functions in immune response, inflammation, and stress response, as well as those involved in influenza pathogenesis and melatonin degradation pathways that appear to be indicative of gain and intake phenotypes in beef steers. Technical Abstract: Small intestine mass and cellularity have previously been associated with cattle feed efficiency. The small intestine is responsible for digestion of nutrients and absorption of fatty acids, amino acids and sugars and contributes to the overall feed efficiency of cattle. The objective of this study was to evaluate transcriptome differences among the small intestine from cattle with divergent gain and feed intake. Animals most divergent from the bivariate mean in each of the four phenotypic Cartesian quadrants for gain x intake were selected and the transcriptomes of duodenum, jejunum and ileum were evaluated by microarray. Gene expression analyses were performed comparing high gain versus low gain animals, high intake versus low intake animals, and comparing each of the phenotypic quadrants to each of the other groups. Gene groups differentially expressed within the most efficient and least efficient groups of animals included those involved in immune function, inflammation and transcription. The high gain-high intake group differed from other groups by immune response genes and ribosomal genes. The animals with low gain-low intake displayed greater abundance of heat shock genes compared to all other groups of animals. Several over–represented pathways were identified. These included antigen processing/presentation pathway in high versus low gain animals and PPAR signaling, starch/sucrose metabolism and the retinol metabolism pathway in the high versus low intake animals. In summary, we have identified genes with functions in immune response, inflammation, stress response, influenza pathogenesis, and melatonin degradation pathways that appear to be indicative of gain and intake in beef steers. |