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:12 Holstein dairy heifers were limit-fed with high or low forage diets, and integrative hepatic metabolomics and proteomics were used to reveal insights into the mechanism of different feed efficiency behind that.
Project description:Liver plays a profound role in the acute phase response (APR) observed in the early phase of acute bovine mastitis caused by Escherichia coli (E. coli). To gain an insight into the genes and pathways involved in hepatic APR of dairy cows we performed a global gene expression analysis of liver tissue sampled at different time points before and after intra-mammary (IM) exposure to E. coli lipopolysaccharide (LPS) treatment. Experiment Overall Design: Eight healthy, high yielding Holstein-Friesian dairy cows in their first lactation (9 to 12 weeks after calving) were chosen for this study. At time 0 the right front quarter was infused with 200 μg E. coli LPS dissolved in 10 ml 0.9% NaCl solution, the left front quarter serving as control was infused with 10 ml 0.9% NaCl solution. Liver biopsies were taken at â22, 3, 6, 9, 12 and 48 hours relative to LPS infusion in 4 cows, and also at â22, 9 and 48 hours in the remaining 4 cows. RNA from liver biopsies was isolated and biotin labeled cRNA was loaded onto the Affymetric GeneChip Bovine Genome Array. A control study using cows infused with 0.9% NaCl showed that there was no effect of taking the biopsy, neither in the clinical measurement nor in the expression of a selected subset of genes. Therefore, only samples taken from the LPS treated cows were measured for the gene expression using microarrays.
Project description:Evaluate the influence of maternal metabolism on gene expression profiles from extra-embryonic tissues at D18 Keyword: Holstein Heifers and Postpartum dairy cows, metabolism and energy status, elongation and gastrulation, extra-embryonic tissues, transcriptome, correlations between genes & metabolites?
Project description:The experiment is part of a study aimed at identifying and studying genes that contribute to differences in oestrous behaviour expression and fertility levels of dairy cows. Samples from 4 brain areas (dorsal hypothalamus, ventral hypothalamus, amygdala and hippocampus) and the anterior pituitary were collected from 28 primiparous Holstein Friesian cows, 14 of which were sacrificed at start of oestrus and 14 at mid of oestrous cycle. Differential gene expression between the 2 phases of oestrous cycle as well as the association of gene expression patterns with the level of oestrous behaviour expression are studied.
