Effects of Complete Ensiled Ration on Milk Production, Milk Composition, and Rumen Environment of Dairy Cattle

Abstract

Corn silage from the same field was stored in two upright silos. The silage in the first silo contained no additive and was the control. In the second silo, a complete ensiled ration was developed by blending concentrate mixture with chopped corn at ensiling to attain a 60:40 forage to concentrate ratio of dry matter. As fed 1kg of concentrate mixture was blended with every 4.55kg of wet forage. The complete ensiled ration was 39.0% dry matter and the mean proximate composition (dry matter) was 15.2% crude protein, 18.2% crude fiber, 1.54 Mcal/kg estimated net energy, 75.2% total digestible nutrients, .60% calcium, and .47% phosphorus. The complete ensiled ration went through a normal fermentation with no signs of heating, molding, or deterioration.Two groups of 10 Holstein cows were assigned to treatments in a double reversal experiment with three 28-day periods. The two rations fed were complete ensiled ration ad libitum and corn silage fed ad libitum with the concentrate portion fed individually at each milking. No differences were significant in dry-matter intake, mean daily fat-corrected-milk yields, percent milk fat, protein, or total solids.Higher concentrations of volatile fatty acids were produced by cows on the complete ensiled ration (95.2μmol/ml) as compared to cows on the control ration (85.4μmol/ml). Protozoa population was 7.0×105 and 7.8×105 per ml rumen fluid for the control and experimental groups.