Effect of corn snaplage on lactation performance by dairy cows

The objective of this study was to determine lactation performance by dairy cows fed corn snaplage either alone (SNAP) or in combination with ground dry shelled corn (SPDC) versus rolled high-moisture shelled corn (RHMC). Dry-matter content was greater for RHMC (78.2%) than SNAP (68.5%). The starch content of SNAP was approximately 10%-units lower than RHMC. Sixty Holstein cows (30 primiparous and 30 multiparous; 100 ± 23 DIM and 626 ± 44 kg of BW at trial initiation) were used in a randomized, complete-block, continuous-lactation trial: 2-wk covariate adjustment period with all cows fed a 50:50 mixture (DM basis) of SNAP and RHMC in TMR followed by an 8-wk experimental period with cows fed their assigned treatment corn grain (RHMC, SNAP, or SPDC) in TMR. Intake of DM was reduced by 2.6 kg/d per cow, on average, for SNAP and SPDC compared with RHMC. Milk yield averaged 39.4 kg/d per cow and was unaffected by treatment as were all measures of component-corrected milk yield. Actual milk, FCM, solids-corrected milk, and energycorrected milk feed efficiencies (kg/kg) were greater, on average, for SNAP and SPDC compared with RHMC by 7 to 9%. Milk fat percentage was reduced by 0.27% units, and milk-urea-nitrogen concentration was greatest, for SNAP compared with RHMC. These changes in milk composition along with reduced DMI were likely related to greater ruminal starch digestibility for SNAP. Milk fat and milk-urea-nitrogen concentrations were improved by the partial replacement of SNAP with ground dry shelled corn in the SPDC treatment.