Dietary effects of linseed on fatty acid composition of milk and on liver, adipose and mammary gland metabolism of periparturient dairy cows

Abstract

SummaryDuring the transition period in dairy cows, drastic adaptations within and between key tissues and cell types occur in a coordinated manner to support late gestation, the synthesis of large quantities of milk and metabolic homoeostasis. The start of lactation coincides with an increase of triacylglycerols in the liver, which has been associated with several economically important diseases in dairy cows (i.e. hepatic lipidiosis, mastitis). The polyunsaturated fatty acids have been used to improve liver metabolism and immune function in the mammary gland. Therefore, the effects of dietary linseed supplementation on milk quality and liver, adipose and mammary gland metabolism of periparturient dairy cows were studied in 14 cows that were randomly assigned to control or linseed supplementation. Animals were treated from 3 weeks antepartum until 6 weeks post-partum. Linseed did not modify dry matter intake, but increased milk yield and lactose yield, and decreased milk fat concentration, which coincided with lower proportion of C16 and higher proportions of stearic acid, conjugated linoleic acid and a-linolenic acid in milk fat. Linseed supplementation did not significantly change the expression of key lipid metabolism genes in liver and adipose tissues, except of glucose transporter 2 (GLUT2) in liver, which was increased in cows supplemented with linseed, suggesting that more glucose was secreted and probably available for lactose synthesis compared with cows fed control diet. Large adaptations of transcription occurred in the mammary gland when dairy cows were supplemented with linseed. The main affected functional modules were related to energy metabolism, cell proliferation and remodelling, as well as the immune system response.

Effect of linseed oil supplementation on performance and milk fatty acid composition in dairy cows

“…A major concern in using linseed in animal feeding is potential negative effects of FA from linseed on feed intake and animal performance. The intakes of DM, CP and net energy for lactation at the production level (NE LP ) in this study were in agreement with most literature reports that showed little effects of concentration and type of fat supplement when total fat concentration was below 6% of DM (Dirandeh et al ; Mach et al ). The effect of unsaturated fat including LSO supplementation on intake has been variable among previous studies.…”

Bovine Mammary Nutrigenomics and Changes in the Milk Composition due to Rapeseed or Sunflower Oil Supplementation of High-Forage or High-Concentrate Diets

“…This is in line with the large adaptation of mammary transcription to linseed supplementation affecting the energy metabolism, cell proliferation and remodeling as well as the immune system response reported by Mach et al [30]. However, the number of genes involved in the pathways related to the biosynthesis and secretion of milk components was not particularly large in the DEG list.…”

“…The affiliation of these genes with the zinc finger family suggested that they function in the regulation of the transcription, as observed for ZNF821 , which contains a domain reported to be a novel DNA-binding motif [29]. Moreover, ZNF653 has recently been characterized as a novel protein affecting transcription through the mediation of several nuclear receptors, such as peroxisomal proliferator-activated receptor gamma, which is known to mediate the expression of lipogenic genes and to be negatively correlated with the concentration of trans -FA and CLA isomers in milk [30]. Finally, the replication, transcription and translation class also contained 2 genes (RNASE4 and RBM5) involved in RNA processing.…”

Comparison between stearoyl‐CoA desaturase expression in milk somatic cells and in mammary tissue of lactating dairy cows

“…Cows were group‐housed in a cubicle shed with continuous access to water and were milked twice daily at 06:00 and 17:00 hours. Experimental treatments started 3 weeks before the expected calving date and lasted until 6 weeks after calving (Mach et al., 2011).…”