Project description:Cattle are often fed high concentrate diets to increase energy intake and improve overall animal performance. Such diets also cause changes in fermentation patterns and epithelial function. However, the molecular mechanisms involved in regulating epithelial function for cattle fed high concentrate diets have not been elucidated. In this study, we aimed to gain a broad overview of the involved molecular mechanisms by detecting differentially expressed genes (DEG) in rumen tissue from dairy cows fed a low concentrate (LC; 8%) compared to a high concentrate (HC; 64%) diet using a bovine-specific microarray platform containing 16,846 unique gene loci and 5,943 ESTs from the bovine genome. Feeding the HC diet increased the total volatile fatty acid concentration and markedly reduced ruminal pH, suggesting that the dietary treatments used did induce changes in ruminal fermentation. In response to changes in the ruminal environment, a total of 5,200 elements were detected as DEG in ruminal tissue with >1.5-fold expression change (P < 0.05) for cows fed HC relative to LC. Of the 5,200 DEG, 2,233 and 2,967 were up- and down-regulated, respectively. The GENECODIS analysis elucidated that relationships among the DEG represented 19 annotations characterized with GO molecular function and KEGG pathways with 26 DEG identified in multiple annotations such as calcium signaling and gap junction pathways. Among those DEG that were identified numerous times, catalytic subunit of cAMP-dependent protein kinase (PRKACB) was down-regulated in ruminal tissue from cows fed HC, suggesting that this gene may have important roles including regulation of cell proliferation and differentiation, and intracellular pH regulation. Two-condition experiment, High concentrate vs. Low concentrate diets. Biological replicates: 5 high concentrate fed, 5 low concentrate, independently grown and harvested. Two replicates per array.
Project description:Cattle are often fed high concentrate diets to increase energy intake and improve overall animal performance. Such diets also cause changes in fermentation patterns and epithelial function. However, the molecular mechanisms involved in regulating epithelial function for cattle fed high concentrate diets have not been elucidated. In this study, we aimed to gain a broad overview of the involved molecular mechanisms by detecting differentially expressed genes (DEG) in rumen tissue from dairy cows fed a low concentrate (LC; 8%) compared to a high concentrate (HC; 64%) diet using a bovine-specific microarray platform containing 16,846 unique gene loci and 5,943 ESTs from the bovine genome. Feeding the HC diet increased the total volatile fatty acid concentration and markedly reduced ruminal pH, suggesting that the dietary treatments used did induce changes in ruminal fermentation. In response to changes in the ruminal environment, a total of 5,200 elements were detected as DEG in ruminal tissue with >1.5-fold expression change (P < 0.05) for cows fed HC relative to LC. Of the 5,200 DEG, 2,233 and 2,967 were up- and down-regulated, respectively. The GENECODIS analysis elucidated that relationships among the DEG represented 19 annotations characterized with GO molecular function and KEGG pathways with 26 DEG identified in multiple annotations such as calcium signaling and gap junction pathways. Among those DEG that were identified numerous times, catalytic subunit of cAMP-dependent protein kinase (PRKACB) was down-regulated in ruminal tissue from cows fed HC, suggesting that this gene may have important roles including regulation of cell proliferation and differentiation, and intracellular pH regulation.
Project description:The liver of dairy cows naturally displays a series of metabolic adaptation during the periparturient period in response to the increasing nutrient requirement of lactation. The hepatic adaptation is partly regulated by insulin resistance and it is affected by the prepartal energy intake level of cows. We aimed to investigate the metabolic changes in the liver of dairy cows during the periparturient at gene expression level and to study the effect of prepartal energy level on the metabolic adaptation at gene expression level.B13:N13
Project description:The objective of this project is identifying differentially expressed (DE) genes which are associated with higher omega-3 fatty acids deposition in beef cows. Omega-3 fatty acids have been found to influence meat flavor and are beneficial to human health. Supplementation of livestock diets with flaxseed, a rich source of ë±-linolenic acid, is the most common means of producing omega-3 fatty acid-enriched animal products. Towards the goal of enhancing beef fatty acid composition, 64 crossbred cull cows (~30 months of age) with similar breed composition were randomized by weight/body condition, and fed one of four 50:50 forage:concentrate diets on a DM basis (16 cows/treatment), containing ground barley grain with either hay or silage, supplemented with 0 or 15% ground flaxseed (DM basis). Cows were slaughtered after spending 140 days on the treatment diets. Five cows from each of the four diets were selected for transcriptional analysis based on FA profiles of the kidney fat collected at slaughter. RNA was isolated from Longissimus thoracis muscle, subcutaneous and kidney fat of each cow (20 samples/tissue) and hybridized in duplicate to BOMC 24K 60-mer microarrays. Differential gene expression between flax-fed and non-flax-fed cows as well as identifying those genes associated with fatty acid metabolism were studied.
Project description:The objective of this study was to characterize the mRNA expression profile in rumen epithelium from Holstein dairy cows fed high or low concentrate dits.
Project description:Twelve midlactation cows received 4 diets differing in forage-to-concentrate ration (High (HF) versus Low (LF) forage supplemented or not with lipids (HF with whole intact rapeseeds (HF-RS) and LF with sunflower oil (LF-SO))
Project description:Twelve midlactation cows received 4 diets differing in forage-to-concentrate ration (High (HF) versus Low (LF) forage supplemented or not with lipids (HF with whole intact rapeseeds (HF-RS) and LF with sunflower oil (LF-SO)) 12 cows got into 4 groups, each cow was received 4 different diets in a latin square design Green*txt and Red_*txt raw data files contain Cy3 and Cy5 signal intensities, respectively.