Project description:High yielding dairy cattle undergo a state of NEB (negative energy balance) during the post-partum period when energy demand for lactation and maintenance exceeds energy intake. During this period in order to counteract NEB the liver under goes extensive metabolic and physiological change resulting in alteration in hepatic genes and miRNAs expression. We used Affymetrix Multispecies miRNA-2_0 Array with miRBase version 15 coverage to assess the liver miRNA expression in SNEB (severe NEB) and MNEB (mild NEB) Holstein Friesian cattle during the post-partum period. A NEB model of Holstein Friesian was established such that 12 post-partum cattle were randomly assigned to MNEB and SNEB groups depending on different feeding and milking regimes
Project description:High yielding dairy cattle undergo a state of NEB (negative energy balance) during the post-partum period when energy demand for lactation and maintenance exceeds energy intake. During this period in order to counteract NEB the liver under goes extensive metabolic and physiological change resulting in alteration in hepatic genes and miRNAs expression. We used Affymetrix Multispecies miRNA-2_0 Array with miRBase version 15 coverage to assess the liver miRNA expression in SNEB (severe NEB) and MNEB (mild NEB) Holstein Friesian cattle during the post-partum period.
Project description:miRNA profiling of bovine satellite cells (BSC) differentiated into myotubes (6th day of in vitro differentiation). BSC isolated from m. semitendinosus of beef (Hereford & Limousine) and dairy (Holstein-Friesian) cattle. Goal was to determine differences in miRNA expresion during in vitro myogenesis in beef vs dairy cattle used as a control.
Project description:This experiment was undertaken to document changes in gene expression in the skin of tick-resistant Brahman (Bos indicus) and tick-susceptible Holstein-Friesian (Bos taurus) cattle prior to, and following, infestation with the cattle tick Rhipicephalus (Boophilus) microplus Experiment Overall Design: RNA was extracted from skin samples of tick-naïve cattle (animals with no previous R.microplus exposure) and tick-infested cattle after a period of successive, heavy infestations with R. microplus. Skin samples taken from tick-infested animals were taken at sites where tick larvae (approximately 24 h old) were attached to the skin sample. Skin samples were of 8 mm diameter and full skin thickness (approximately 10 mm). RNA samples from 12 animals (3 tick-naive Holstein-Friesian, 3 tick-naive Brahman, 3 tick-infested Holstein-Friesian and 3 tick-infested Brahman) were processed and hybridised to individual slides.
Project description:This trial was undertaken to examine the perhipheral cellular and antibody response of cattle following infestation with the cattle tick, Rhipicephalus microplus. The information from the Affymetrix gene expression data is used to complement other measurements of immune function such as cellular subset composition and antibody response in cattle of high (Brahman) and low (Holstein-Friesian) resistance to the cattle tick. Experiment Overall Design: RNA was extracted from white blood cells during a period of successive, heavy infestations with R. microplus. RNA samples from 3 Holstein-Friesian and 3 Brahman animals were analysed on individual slides.
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 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.
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.