THE EFFECT OF MOISTURE CONTENT OF FORAGE STORED IN POLYVINYL SILOS ON INTAKE AND PERFORMANCE OF DAIRY COWS

Abstract

Legume–grass forage was ensiled two seasons in 25-ton polyvinyl-encased stacks at dry matter (D.M.) levels of 22 to 37% or stored as field-cured hay. The polyvinyl sleeve coverings provided initial gas-tight conditions. High losses occurred in the high D.M. (32 to 37%) silage during the feeding-out period. Silage quality, as indicated by volatile fatty acid ratios, proximate principles, and digestibility coefficients, was not significantly influenced by D.M. content. When cows were fed the lower D.M. (22 to 29%) silages and hay, forage intake was inversely related to its dry matter content. Intake of high D.M. silage appeared abnormally low. Milk yields appeared to be more consistently influenced by small variations in grain intake than forage dry matter intake through both trials. Milk yields from silages were greater than from hay per unit of D.M. intake. Moisture content of forage had no significant effect on milk composition as indicated by percentage of butterfat, solids-not-fat, or protein.