A Comparison of On-Farm Methods for Estimating the Dry Matter Content of Feed Ingredients

On-fann methods for determining the DM content of ensiled feed ingredients were evaluated to determine ease of use time required to conduct the determinat ion, repeatability, and accuracy relative to a standard drying method. Methods e~aluated were sequential drying in a mIcrowave oven, Koster tester method, and electronic moisture tester method. A drying oven was used as the standard drying method. Feed ingredients evaluated were alfalfa silage, corn silage, and high moisture shelled com (unground k~rnels). All on-fann methods gave hIghly repeatable DM results. The microwave oven method was more accurate than the standard method but required the most time to perform. The Koster tester tended to underdry feed ingredients and was not as repeatable as the microwave method. The electronic moisture tester was comparable with the other on-fann methods for alfalfa silage and most closely agreed with the standard method for high moisture shelled com. However, compared with the standard method, the electronic moisture tester did not accurately determine the DM content of com silage. The electronic moisture tester required the least operator skill and time.