Z. Wang, M. L. Eastridge1, and X. Qiu
The Ohio State University Department of Animal Sciences
Sixty Holstein cows were assigned to two treatments at 21 days before calving and were group fed a prepartum diet with or without yeast culture (YC). Cows fed YC prepartum also were fed YC postpartum (60 g/day). After parturition, cows were individually fed one of five treatments for 140 days: (1) 21% forage NDF (FNDF) without YC, (2) 21% FNDF with YC, (3) 17% FNDF without YC, (4) 17% FNDF with YC, and (5) 25% FNDF with YC for 30 days then switched to Diet 4 for 110 days. A quadratic response to 25, 21, and 17% FNDF occurred during the first 30 days in milk (DIM) for DM intake, milk yield, and milk protein yield. No differences were observed for YC or interaction of YC and forage NDF for the first 30 DIM. Feeding 17 vs. 21% FNDF increased milk protein percentage and tended to increase DM intake as a percentage of body weight (BW) from 31 to 140 DIM. During this time period, YC tended to increase milk fat percentage and appeared to have positive effects on DM intake, milk yield, and milk fat yield when supplemented to diets with 21% FNDF but not with 17% FNDF. Feeding 17% FNDF may be too low for the first 30 DIM but may improve animal performance after 30 DIM compared to 21% FNDF.
1 For more information, contact at: The Ohio State University, 221B Animal Science Building, 2029 Fyffe Road, Columbus, OH 43210, 614-688-3059, Fax 614-292-1515, e-mail: eastridge.1@osu.edu