Due to numerically higher milk fat percentage, SC cows
produced 1.8 kg more FCM per day. Similarly, Putnam et al.
(1997) showed that 4% FCM of cows in early lactation
tended to increase (28.4 vs. 26.5 kg) when diets were
supplemented with 10 g/d of a yeast culture. Also in the
study of Wang et al. (2001), amounts of milk and FCM
during the first 30 days in milk were 2.5 kg higher in cows
receiving a yeast culture supplement in diets containing
21% forage NDF. Numerical increases in milk fat
percentage have been observed after yeast supplementation
in some trials with dairy cows (Piva et al., 1993; Robinson,
1997; Erasmus et al., 2005). Increased digestibility of NDF
in the SC treatment explains the 0.2 percentage unit
increase in milk fat percentage observed in this trial.