Feeding Value of High Dry Matter Corn Silage for Dairy Cattle

Abstract Two feeding trials using 20 cows each compared high dry matter corn silage (HDMCS) with corn silage of medium dry matter content (MDMCS). A continuous design was employed in Trial I and a double-reversal design in Trial II. The high dry matter corn silage was ground before ensiling and both silages stored in gas-tight units. Significant differences associated with the harvesting of high dry matter corn silage when compared with the medium dry silage include: lower dry matter yields; greater field dry matter losses; higher percentage of ear losses; lower carotene content; lower total acid concentration during fermentation; and a higher pH. Voluntary dry matter consumption, milk production, and body weight gains were greater for cows fed the high dry matter corn silage, but differences were significant only for Trial II. There were no significant differences in per cent milk fat or solids-not-fat between treatments. No consistent difference in chemical composition of the silages between years was found. The digestibility of the dry matter, energy, and protein for the medium and high dry matter silages was 66.9, 66.7, and 54.7; and 64.7, 65.4, and 51.1%, respectively. The silages were nearly equal in feed value; however, the disadvantages suggest that general recommendations for delaying harvest were not warranted.