Productive performance of Holstein calves fed different quality alfalfas and fibrolytic enzyme supplements during the pre and postweaning period

Abstract

The effect of fibrolytic enzyme (FE) supplements and alfalfa quality (i.e. fiber content) on calf productive performance, apparent feed digestibility, and rumen development during the pre- and post-weaning period was evaluated. Before weaning, calves were fed daily 4 L of milk (MI) and solid feed (starter concentrate (SC) + alfalfa hay) ad libitum. Thirty-six, Holstein calves (3 to 7 d of age) were distributed in a random block design with six treatments: 1) MI-SC + low-fiber alfalfa, 2) treatment 1 + FE, 3) MISC + medium-fiber alfalfa, 4) treatment 3 + FE, 5) MI-SC + high-fiber alfalfa, and 6) treatment 5 + FE. Experimental period was 105 d and animals were weaned at d 60. The FE supplement improved (P<0.05) daily weight gain (DWG) (610 g vs 404 g/d) and feed efficiency (FEF) (0.55 vs 0.41) in the preweaning stage. Final dry matter intake (DMI) tended (P<0.05) to be higher (1.99 vs 1.65 kg d-1) in the animals that consumed FE-supplemented feed. Alfalfa fiber content did not affect DWG, DMI or final FEF (P>0.05). Apparent feed digestibility was similar among treatments (P>0.05) for dry matter (DM), crude protein (CP), and neutral detergent fiber (NDF). There were significant differences (P<0.05) between the preweaning and postweaning periods in the digestibility coefficients for DM (81.5 vs 70.8 %), CP (72.5 vs 62.3 %) and NDF (81.9 vs 45.3 %). Ruminal volatile fatty acid concentration, rumen papillae size, and rumen, abomasum, and intestine digesta viscosity exhibited no significant differences (P>0.05) among treatments. Inclusion of FE improved daily weight gain and feed efficiency in the preweaning period.