Project description:The aim of this study was to determine the effects of unprotected dietary unsaturated fatty acids (UFA) from different plant oils on gene expression in the mammary gland of grazing dairy cows. Milk composition and gene expression in the mammary gland tissue were evaluated in grazing dairy cows supplemented with different unsaturated fatty acids (UFA). The UFA supplementation improves the health and nutrition quality aspects of dairy milk, but also affects the gene networks expression signature associated with cellular growth and proliferation, cell-death, signalling, nutrient metabolism, and immune response, and in turn, the mammary gland integrity and health. SUBMITTER_CITATION: Mach, N., A. A. A. Jacobs, L. Kruijt, J. Van Baal, and M. A. Smits. 2011. Alteration of gene expression in mammary gland tissue of dairy cows in response to dietary unsaturated fatty acids. Animal.DOI:10.1017/S1751731111000103
Project description:The aim of this study was to determine the effects of unprotected dietary unsaturated fatty acids (UFA) from different plant oils on gene expression in the mammary gland of grazing dairy cows. Milk composition and gene expression in the mammary gland tissue were evaluated in grazing dairy cows supplemented with different unsaturated fatty acids (UFA). The UFA supplementation improves the health and nutrition quality aspects of dairy milk, but also affects the gene networks expression signature associated with cellular growth and proliferation, cell-death, signalling, nutrient metabolism, and immune response, and in turn, the mammary gland integrity and health. A total of 28 Holstein-Friesian dairy cows in mid-lactation were blocked according to parity (2.4 ± 0.63 years), days in milk (DIM; 153 ± 32.8 days), milk yield (25.7 ± 3.08 kg/d) and fat content (4.3 ± 0.12%). Cows were then randomly assigned to four UFA-sources based on rapeseed, soybean, linseed or a mixture of the three oils for 23 days (Period I) after which, all 28 cows were switched to a control diet for an additional 28 days (Period II). On the last day of both periods, mammary gland biopsies were taken to study genome-wide differences in lipid metabolism gene expression.
Project description:The aim of the present study was to correlate lipid metabolism genes in the mammary gland tissue affected by stage of lactation and nutrition to the resulting milk fatty acids composition in grazing dairy cows, and to classify milk fatty acid (FA) groups based on variations in lipid metabolism gene expression patterns. Identifying the relationship between lipid metabolism genes in the mammary gland tissue and the resulting milk fatty acid composition is expected to greatly contribute to our understanding of milk fatty acid metabolism and to enhance opportunities to improve milk fat composition through nutrition. In fact, SNCA, SCD5, and PNPLA2 lipid metabolism-related genes affected by unsaturated fatty acids supplementation, were found to strongly correlated to different milk FA groups, but also contributed most to the classification of these FA groups, suggesting a significant role in mediating the lipid metabolism in the mammary gland tissue and determining the milk fatty acids composition. A total of 28 Holstein-Friesian dairy cows in mid-lactation were blocked according to parity (2.4 ± 0.63 years), days in milk (DIM; 153 ± 32.8 days), milk yield (25.7 ± 3.08 kg/d) and fat content (4.3 ± 0.12%). Cows were then randomly assigned to four UFA-sources based on rapeseed, soybean, linseed or a mixture of the three oils for 23 days (Period I) after which, all 28 cows were switched to a control diet for an additional 28 days (Period II). On the last day of both periods, mammary gland biopsies were taken to study genome-wide differences in lipid metabolism gene expression.
Project description:The aim of the present study was to correlate lipid metabolism genes in the mammary gland tissue affected by stage of lactation and nutrition to the resulting milk fatty acids composition in grazing dairy cows, and to classify milk fatty acid (FA) groups based on variations in lipid metabolism gene expression patterns. Identifying the relationship between lipid metabolism genes in the mammary gland tissue and the resulting milk fatty acid composition is expected to greatly contribute to our understanding of milk fatty acid metabolism and to enhance opportunities to improve milk fat composition through nutrition. In fact, SNCA, SCD5, and PNPLA2 lipid metabolism-related genes affected by unsaturated fatty acids supplementation, were found to strongly correlated to different milk FA groups, but also contributed most to the classification of these FA groups, suggesting a significant role in mediating the lipid metabolism in the mammary gland tissue and determining the milk fatty acids composition.
Project description:The aim of this study was to determine the effects of linseed dietary supplementation on gene expression in the mammary gland of grazing dairy cows. Milk composition and gene expression in the mammary gland tissue were evaluated in dairy cows supplemented with linseed. The linseed supplementation improves the health and nutrition quality aspects of dairy milk, but also affects the gene networks expression signature associated with cellular growth and proliferation, cell-death, signalling, nutrient metabolism, and immune response, and in turn, the mammary gland integrity and health.
Project description:The aim of this study was to determine the effects of linseed dietary supplementation on gene expression in the mammary gland of grazing dairy cows. Milk composition and gene expression in the mammary gland tissue were evaluated in dairy cows supplemented with linseed. The linseed supplementation improves the health and nutrition quality aspects of dairy milk, but also affects the gene networks expression signature associated with cellular growth and proliferation, cell-death, signalling, nutrient metabolism, and immune response, and in turn, the mammary gland integrity and health. The experiment was carried out in a complete randomized blocked designed structure comprising 14 Holstein-Friesian cows (6 second parity, 2 third parity and 6 older cows), selected from a 550-cow herd. Cows were paired in 7 blocks on the basis of similarity in parity (second parity, third parity and older cows), expected date of calving, and milk performance in the previous lactation (in order of priority). Cows within each block were randomly allocated to one of two treatment groups, “Omega” or “Control”. The dietary Omega treatment consisted of a basal diet supplemented with a concentrate-mixture including linseed on a dry matter (DM) basis, whereas cows in treatment group Control were supplemented with a concentrate mixture without linseed. Linseed was chosen because it is rich in c9,c12,c15-18:3 (ALA). Concentrate mixtures were fed with a concentrate dispenser. Experimental treatments started 3 weeks before the expected calving date (wk -3) and lasted until 6 weeks after calving (wk 6).
Project description:The objective of this study was to determine the effect of the DGAT1 K232A polymorphism on the global mRNA expression pattern of genes in the mammary gland tissue of grazing dairy cows in order to get more insight into the effects of this polymorphism on the physiology of the mammary glandgland of grazing dairy cows. Microarray analysis was used to identify genes whose expression was affected by the DGAT1 polymorphism in the mammary gland biopsies of 9 A232A cows, 13 K232A cows, and 4 K232K cows. The Microarray Analysis of Variance (MAANOVA) and Factor Analysis for Multiple Testing method (FAMT) were used to associate the expression of the genes present on Affymettrix Bovine Genome Arrays with the DGAT1 polymorphism. The data was also analysed at the level of functional modules by gene set enrichment analysis. In this experimental setting, DGAT1 polymorphism did not modify milk yield and composition significantly, although changes occurred in the yields of C14:0, C16:1cis-9, and some long chain fatty acids in milk. The DGAT1 polymorphism resulted in 30 differentially expressed genes related to cell growth, proliferation and development, signalling, remodelling and immune system. At the functional level, the pathways most affected by DGAT1 polymorphism were related to lipid biosynthesis, which likely reflected counter mechanisms of mammary tissue to respond to changes in milk FA composition, signalling, as well as immune system responses.
Project description:The mammary gland redeveloped to the pre-pregnancy state during involution, which shows that the mammary cells have the characteristics of remodeling. The rapidity and degree of mammary gland involution are different between mice and dairy livestock (dairy cows and dairy goats). However, the molecular genetic mechanism of involution and remodeling of goat mammary gland has not yet been clarified. Therefore, this study carried out the RNA-sequencing of nonlactating mammary gland tissue of dairy goats in order to reveal the transcriptome characteristics of nonlactating mammary tissues and clarify the molecular genetic mechanism of mammary cell involution and remodeling.
Project description:The severity of negative energy balance (NEB) in high-producing dairy cows has a high incidence among health diseases. The periparturient period is crucial for the health status and reproductive performance of dairy cows. During this period, dairy cows experience a transition from a pregnant, non-lactating state to a non-pregnant, lactating state. At the beginning of lactation, the energy needs for milk production are higher than the available energy consumed from feed intake, resulting in a negative energy balance (NEB)]. While in a NEB, cows mobilise their reserves from adipose tissue, resulting in elevated plasma concentrations of non-esterified fatty acids (NEFAs), which are used as a fuel source by peripheral tissues and the mammary gland for milk fat synthesis. Thus, white adipose tissue is one of the main tissue involved in the energy production during this transition period. So the objectives of our study were to dentify mRNA differentially expressed in white adipose before and after calving in dairy cow fed with low (LE) and high (HE) energy diet.