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:We explored the effect of long-term high-concentrate diet feeding on ruminal pH and fermentation, and its effect on the rumen epithelial transcriptomes in Japanese Black beef cattle during a 20-month fattening period.
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:Growth plate chondrocytes were isolated from the distal metacarpus of young dairy cattle (all under 10 mo of age), the chondrocytes were released from the extracellular matrix by digestion with Collagenase P for 4 hours, and the various zones of the growth plate were separated by density centrifugation. The least-dense Hypertrophic Zone (HZ) cells were compared to the most-dense Reserve Zone (RZ) cells. 6 pairs of HZ vs RZ were compared by microarray. Experiment Overall Design: Growth plate chondrocytes were isolated from the distal metacarpus of young dairy cattle (all under 10 mo of age), the chondrocytes were released from the extracellular matrix by digestion with Collagenase P for 4 hours, and the various zones of the growth plate were separated by density centrifugation. The least-dense Hypertrophic Zone (HZ) cells were compared to the most-dense Reserve Zone (RZ) cells. Six independent sample pairs of HZ vs RZ were compared by microarray.
Project description:Four mature, non-lactating dairy cattle were transitioned from a high forage diet (HF; 0% grain) to a high grain diet (HG; 65% grain) that was fed for three weeks. Rumen papillae biopsies were performed during the HF baseline (week 0) and after the first (week 1) and third week (week 3) of the grain challenge to create a transcript profile for the the short and long-term adaption of the rumen epithelium during ruminal acidosis. Comparison between three weekly means (n=4 for each week, 12 arrays in total)
Project description:Four mature, non-lactating dairy cattle were transitioned from a high forage diet (HF; 0% grain) to a high grain diet (HG; 65% grain) that was fed for three weeks. Rumen papillae biopsies were performed during the HF baseline (week 0) and after the first (week 1) and third week (week 3) of the grain challenge to create a transcript profile for the the short and long-term adaption of the rumen epithelium during ruminal acidosis.