Effects of a moderate-energy diet during the close-up dry period on immunometabolic indices in peripartal dairy cows

The peripartal period is characterized by marked changes in hormonal, metabolic, and immune/stress-like conditions all of which may contribute to regulating dry matter intake (DMI) and the supply of nutrients to mammary gland. Twenty three multiparous Holstein cows were fed a control diet (CE, n = 10; 1.24 Mcal/kg DM; high-straw) during the entire dry period (ca. 50 d) or were switched to a moderate-energy (ME, n = 13; 1.47 Mcal/kg DM) diet during the last 21 d prepartum through calving. All cows were fed a common lactation diet (1.67 Mcal/kg DM postpartum). Blood samples were collected at -21, -10, 7, 14, and 21 DIM for profiling of 21 markers of liver function, metabolism, oxidative stress, and inflammation. Concentration of cholesterol (CHOL) and the negative acute-phase protein albumin (ALB) decreased (time P < 0.05) through calving but CHOL increased markedly between 7 and 21 DIM regardless of treatment. Paraoxonase concentration through calving followed a similar pattern (time P < 0.01) as CHOL and ALB; however, concentration remained unchanged from 7 to 21 DIM. Glutamic-oxaloacetic transaminase (GOT) and bilirubin (BIL) concentration increased (time P < 0.01) from -21 to 7 DIM regardless of treatment after which it decreased. Concentration of gamma-glutamyl transpeptidase (GGT) tended (treatment × time P = 0.11) to differ due to greater concentration with ME after 7 DIM. The concentration of haptoglobin, an inflammation marker, increased (time P < 0.01) between -21 and -10 DIM after which it remained stable through 7 DIM and decreased gradually by 21 DIM regardless of treatment. In contrast, concentration of ceruloplasmin, another inflammatory marker, increased (time P < 0.01) linearly between -21 and 14 DIM regardless of treatment. The concentration of reactive-oxygen metabolites (ROM; diet P = 0.08) and urea (diet P = 0.07) was greater overall with CE. For ROM, differences between diets were evident at 7 and 14 DIM. The marked increase in haptoglobin at 7 DIM with CE agrees with that of ROM and ceruloplasmin. Overall, preliminary data provide some evidence that plane of dietary energy during the close-up dry period alters immunometabolism