Abstract
The periparturient period is a metabolically demanding time for dairy animals because of increased nutrient requirements for milk yield. The objective of this study was to investigate the effect of feeding Saccharomyces cerevisiae boulardii (CNCM I-1079), a commercial active dry yeast (ADY), in dairy cows on productive and metabolic measures during the periparturient period. Primiparous (n = 33) and multiparous (n = 35) cows were fed a close-up total mixed ration (TMR) before calving and a lactation TMR postpartum. Three weeks before expected calving time, animals were blocked by parity and body weight and then randomly assigned to either control group (control; n = 34) or treatment (ADY; n = 34). All animals were housed in a tie-stall barn with individual feed bunks; the ADY animals received supplementary Saccharomyces cerevisiae boulardii (CNCM I-1079), top dressed daily at a predicted dosage of 1.0 × 1010 cfu (12.5 g) per head. Blood samples were collected weekly along with milk yield and milk composition data; feed intake data were collected daily. Serum samples were analyzed for glucose, nonesterified fatty acid, β-hydroxybutyrate, haptoglobin (Hp), and the cytokines tumor necrosis factor-α, IL-6, and IL-18. Colostrum samples collected within the first 6 to 10 h were analyzed for somatic cell score and IgG, IgA, and IgM concentrations. Data were analyzed using PROC GLIMMIX in SAS with time as a repeated measure; model included time, parity, treatment, and their interactions. The ADY groups had greater milk yield (39.0 ± 2.4 vs. 36.7 ± 2.3 kg/d) and tended to produce more energy-corrected milk with better feed efficiency. There was no difference in plasma glucose, serum nonesterified fatty acid, serum β-hydroxybutyrate, Hp, IL-6, or IL-18 due to ADY treatment. The tumor necrosis factor-α increased in ADY-supplemented animals (1.17 ± 0.69 vs. 4.96 ± 7.7 ng/mL), though week, parity, and their interactions had no effect. Serum amyloid A tended to increase in ADY-supplemented animals when compared to control animals and was additionally affected by week and parity; there were no significant interactions. No difference in colostrum IgG, IgA, and IgM was observed between treatments. Supplementing transition cow TMR with ADY (CNCM I-1079) improved milk production and tended to improve efficiency in early lactation; markers of inflammation were also influenced by ADY treatment, though the immunological effect was inconsistent.