Dose effect of Actisaf Sc 47 yeast probiotic (Saccharomyces cerevisiae) supplementation on production, reproduction, and negative energy balance in early lactation dairy cows

Abstract The study evaluated the dose effect of dietary supplementation with yeast probiotic Saccharomyces cerevisiae (CNCM I-4407, 1010 CFU/g, Actisaf Sc 47; Phileo by Lesaffre, France) on production, energy metabolism, and reproduction in lactating dairy cows. About 117 multiparous Holstein cows from 3 to 60 d in milk held in a barn with an automatic milking system were enrolled in a randomized complete block design and blocked according to calving day, parity, and previous milk yield. The cows were assigned to a basal diet (15% CP, 22% starch) plus either 5 g (Y5 group, n = 39), 10 g (Y10 group, n = 39), or 0 g (CON, n = 39) of yeast probiotic, presented on top of concentrate fed in the robot. Milk yield and body weight were recorded daily, milk composition, and somatic cell count (SSC) every 2 wk, and body condition score (BCS) was estimated at days −14, 14, and 40 post-calving. Data were analyzed using a linear mixed model. The Y10 group showed an increased average daily yield of energy-corrected milk (ECM) over CON (+3.5 kg, P