Expression of selected genes related to energy mobilization and insulin resistance in dairy cows

The physiological and metabolic adaptation characterizing the transition period in the dairy cows is developed by a complex modulation of different metabolic pathways as well as the expression of selected tissue-specific gene. The aim of this study was to evaluate the age effect on expression of selected genes in adipose, hepatic and muscle tissues in dairy cows during their dry period using the quantitative Real Time Polymerase Chain Reaction (qRT-PCR). Twenty-two pluriparous dairy cows were divided into 3 groups in relation to the age: Group A (38 ± 2 months); Group B (52 ± 2 months) and Group C (80 ± 8 months). Lower levels of peroxisome proliferator-activated receptor gamma (PPARG) and higher levels of adiponectin (ADIPOQ) were found in adipose tissue in Group C than Groups A and B (P < 0.05). Higher levels of solute carrier family 2/facilitated glucose transporter member 4 (SLC2A4) were found in muscle in Group C than Group A (P < 0.001) and Group B (P < 0.05). The present study showed in dairy cows that the expression of selected genes associated with mobilization of energy and with insulin resistance are influenced by age demonstrating and highlighting the importance of a genomics approach to assess the metabolic status of dairy cows during the transition period.