July 12, 1996
Clark Presents at National Dairy Conference
UW-River Falls animal science Professor Perry Clark presented a paper at the convention of the American Dairy Science Association at Oregon State University in Corvallis, Ore., July 17.
Clark is a resident of Ellsworth, Wis., and is the son of Ruth Clark of Ellsworth.
Clark's paper was based on a study that concluded that short term use of finely chopped corn silage as a portion of a cow's diet had no negative effects on milk production, milk fat concentration, milk protein concentration or cud chewing.
The study was the fourth study Clark has conducted with Professor L.E. Armentano of UW-Madison. Previous studies concentrated on the use of by-product feeds such as cottonseed, distillers' grains and beet pulp as sources of fiber to replace a portion of the forage in the diet.
The current study involved two separate trials in consecutive years using 15 lactating Holsteins per year. A normal diet containing all of the forage in the form of alfalfa silage was compared to three other diets in which half of the alfalfa silage was replaced by either normal, coarse corn silage or rechopped fine corn silage or an equal mix of the coarse and fine corn silage.
Clark found no difference among the diets in dry matter intake, milk yield, milk protein and fat yields or total daily chewing time. However, a slight trend toward higher milk and fat corrected milk yield was observed as corn silage particle size decreased.
Clark is optimistic about the study, but cautions farmers against chopping forages too fine. "This [finely chopped] corn silage only represented a portion of the diet and smaller particle size may indeed have detrimental effects if fed as a larger percentage of the total diet or continued for longer periods."
Clark recommends farmers follow established guidelines for corn silage chop lengths until long term studies are conducted and evaluated.