Abstract #T144

# T144
Effect of previous milk replacer feeding program on calf performance and digestion from 2 to 4 mo of age.
F. X. Suarez-Mena*1, T. S. Dennis1, T. M. Hill1, W. Hu1, J. D. Quigley1, R. L. Schlotterbeck1, R. N. Klopp2, G.J. Lascano2, L. E. Hulbert3, 1Provimi, Brookville, OH, 2Clemson University, Clemson, SC, 3Kansas State University, Manhattan, KS.

The objective of this study was to evaluate the carry-over effects of 4 milk replacer (MR) feeding programs on calf performance and digestion from 2 to 4 mo of age. Male Holstein calves (n = 96; 75 ± 3.7 kg BW; 57-58 d of age; received in 2 separate groups of 48 calves) were grouped by previous milk replacer program (4 calves/pen): up to 0.66 kg/d DM from MR (0.6KG), up to 0.82 kg/d DM from MR (0.8KG), up to 1.1 kg/d DM from MR (1.1KG), or for ad libitum intake (ADLIB). Total intake of MR for each program averaged 25.3, 35.3, 40.9, and 46.5 kg DM per calf for 0.6KG, 0.8KG, 1.1KG, and ADLIB, respectively. A textured calf starter (20% CP, 39% starch on a DM basis) was mixed with 5% chopped grass hay (6% CP, 64% NDF on a DM basis) and fed for ad libitum intake for the 56 d study. Hip width, BW, and body condition score were measured on d 0, 28, and 56. During d 10–14, fecal samples were taken from the pen floor with care not to sample floor materials and composited by pen for use to estimate diet digestibility using acid insoluble ash. Data were analyzed as a completely randomized design with repeated measures when appropriate and pen was the experimental unit. All pair-wise contrasts were used to separate means. Initial BW was greater (P < 0.05) for 1.1KG and ADLIB vs. 0.6KG and 0.8KG. Hip width change was greater (P < 0.05) for 0.6KG vs. others; ADG for 0.6KG was greater (P < 0.05) than ADG for 1.1KG and ADLIB programs. Intake, body condition score change, and final BW and hip widths did not differ (P > 0.05) among treatments. Digestibility of DM differed for all treatments with 0.6KG >0.8KG >1.1KG > ADLIB. Digestibility of CP was greater (P < 0.05) for 0.6KG vs. other treatments. Digestibility of OM, ADF, and NDF were greater (P < 0.05) for 0.6KG and 0.8KG vs. 1.1KG and ADLIB. Previous milk replacer program influenced performance and feed digestion in calves from to 2 to 4 mo of age. Calves previously fed more milk replacer started with a larger BW at 2 mo but this difference disappeared by 4 mo of age. Feeding more than 25.3 kg of milk replacer pre-weaning can negatively affect performance and digestion from 2 to 4 mo of age.

Key Words: digestibility, post-weaning