RNAseq of circulating neutrophils in peripartal grazing dairy cows divergent in metabolic health

In dairy cows, the transition from dry and pregnant to non-pregnant and lactating creates metabolic and immunological strain, which means many cows succumb to metabolic and infectious disease. This peripartum period, from three weeks pre-calving to three-weeks post-calving, is also known at the transition period. Metabolic health status during the transition period is determined by plasma concentrations of non-esterified fatty acids (NEFA), plasma ß-hydroxybutyrate (BHBA), and liver triacylglycerol (TAG). High concentrations of these indicate cows that are under metabolic stress during the transition period and are, therefore, more likely to experience health conditions, also known as transition failure. Neutrophils, phagocytic cells of the innate immune response, are fundamental for fighting infectious agents.