Impact of direct-fed enzymes and microbials on the health and performance of dairy cows

Key Finding

DFM and enzyme supplementation offer no added benefit, and no effect on colostrum quality and yield, for lactating cows from the prepartum period until 8 weeks postpartum.

About the Co-Author

A photograph of dairy researcher Peter Erickson

Peter Erickson, Professor of Agriculture, Nutrition, and Food Systems

Contact information:
603-862-1341, Peter Erickson Lab website

This research was published in the INSPIRED: A Publication of the New Hampshire Agricultural Experiment Station (Winter 2021)

Researchers: S.B. Ort, K.M. Aragona, C.E. Chapman, A.F. Brito, and P.S. Erickson

Dairy farmers have been using direct-fed microbials (DFMs) for several years in the feeding of dairy cattle. Results include increased feed intake, reduced incidence of ketosis and increased blood antibody concentrations. Supplementing feed with certain enzymes has been shown to increase fiber digestibility, resulting in greater rumen function through enhanced volatile fatty acid production. However, few studies consider the effect of the enzymes cellulases and amylases—with bacteria and yeast supplementation—on colostrum quality and yield.

In this study, we used 36 multiparous Holstein cows (12 per treatment). Cows received either 0 (C), 45.4 g/day of a DFM containing Enterococcus faecium and Saccharomyces cerevisiae (D) or D + 18.2 g/day of an enzyme containing cellulase and amylase.

Cows began the study three weeks before calving and continued for eight weeks postpartum. The prepartum diet was 68.5% forage with approximately 2/3 of the forage being corn silage. This diet averaged 15.8% CP and 42.3 % NDF. The lactating cow diet consisted of a transition diet that was approximately 62% forage, primarily corn silage. This diet was fed for 14 days postpartum. The nutrient analysis was 15.6% CP and 40.6% NDF and 22.5% starch. Beginning on day 15, the lactating cow diet was fed 50% forage (mostly corn silage). This diet contained approximately 16% CP and 38% NDF with 25% starch. Daily feed intakes were taken every day.

On the day of calving, calves were weighed. Blood was sampled for IgG at birth and at one day of age. Colostrum quality (IgG) was determined, and calves were fed their respective dam's colostrum. Colostrum yield varied, ranging from the control cows averaging 10.7 L and the D cows averaging 6.6 L. All colostrum was considered good quality (>50 g IgG/L). However, IgA was different with the D fed cows, producing the least IgA content of 36.8 g/L, in comparison to the C cows, producing 65.6 g/L. Immunoglobulin A is beneficial in fighting against intestinal pathogens. There were no effects of cow treatment on the calf on the day of birth, suggesting that feeding DFM and enzymes did not affect in utero calf development. Milk yield was variable ranging from 96 pounds/day for D cows to 107 pounds/day for the C cows.

These results indicate that, at least in this study, no beneficial effects of DFM and enzyme supplementation were observed from the prepartum period until eight weeks postpartum.

This material is based upon work supported by the NH Agricultural Experiment Station, through joint funding of the National Institute of Food and Agriculture, U.S. Department of Agriculture, under award number 1016574, and the state of New Hampshire. Authors include S.B. Ort, K.M. Aragona, C.E. Chapman, A.F. Brito, and P.S. Erickson

Read the NHAES Dairy Report, Winter 2021