Project description:This SuperSeries is composed of the following subset Series:; GSE15019: Transcriptome analysis of bovine mammary gland tissue treated with E. coli for 6 hours; GSE15020: Transcriptome analysis of bovine mammary gland tissue treated with E. coli for 24 hours; GSE15022: Transcriptome analysis of bovine mammary gland tissue of an udder quarter adjacent to an E.coli treated one for 24 hrs Experiment Overall Design: Refer to individual Series
Project description:Investigation of the bovine mammary gland response to Escherichia coli and Staphylococcus aureus infection. The aims of the study were to examine the dynamics of the mammary gland response to pathogen invasion and identify general and pathogen-specific transcriptional profiles. Individual udder quarters of 12 cows were sequentially inoculated with either E. coli or S. aureus over 24 or 72 hours before culling, whilst one quarter was used as an uninfected control.
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.