Immunometabolic indices in dairy cows supplemented with SmartamineM® or MetaSmart during the peripartal period.

The early postpartal 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. Peripartal cows are in negative Methionine (M) balance due to increased requirements of tissues and cells for methylated compounds and M for milk protein production. Therefore, supplementation of rumen-protected M during the peripartal period may improve yield of milk and protein, and also help coordinate immunometabolic adaptations of the cow. Twenty four multiparous Holstein cows were fed a control diet (ME, n = 8; 1.47 Mcal/kg DM prepartum and 1.67 Mcal/kg DM postpartum), ME plus MetaSmart (MS, n = 8; ADISSEO France S.A.S.), or ME plus Smartamine M® (SA, n = 8; ADISSEO France S.A.S.). All cows received a common diet (1.24 Mcal/kg DM) during the far-off period [-50 to -21 days in milk (DIM)]. Treatments started at -21 DIM and continued through 30 DIM. MetaSmart (0.19% of DM prepartum and 0.18% of DM postpartum) and SA (0.07% of DM prepartum and postpartum) were top-dressed on the ME diet. 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) around calving but increased by 21 DIM regardless of treatment. Paraoxonase concentration followed a similar pattern (time P < 0.01) as CHOL and ALB. Whereas glutamic-oxaloacetic transaminase (GOT) concentration increased (time P < 0.01) from -10 through 21 DIM regardless of treatment, bilirubin (BIL) increased between -10 and 7 DIM and then decreased through 21 DIM. However, the increase in BIL tended (treatment × time P = 0.09) to be lower in cows fed SA. Those responses were indicative of alterations in liver function particularly after calving. The concentration of haptoglobin, inflammation marker, did not change markedly at 7 vs. -21 or -10 DIM and decreased gradually by 21 DIM regardless of treatment. However, cows fed ME tended (P = 0.09) to have greater overall ceruloplasmin concentration due to markedly greater (treatment × time P = 0.03) concentration at -10 DIM. That response was suggestive of a more pronounced inflammatory-like status precalving. Despite an increase (time P < 0.01) in concentration after calving, reactive-oxygen metabolite concentration did not differ between treatments. Overall, preliminary data provide some evidence that M supplementation during the peripartal period could ameliorate inflammatory-like conditions characteristic of this period. As such, M may play a role in stimulating DMI after calving and promoting normal milk production.