FACTORS INFLUENCING DRY MATTER INTAKE AND UTILIZATION OF CORN SILAGE BY LACTATING COWS

Abstract

Moisture content, hay supplementation and energy content of corn silages were studied as factors affecting dry matter (DM) intake and utilization by lactating cows. In experiment I, a two-week delay in date of harvest resulted in an increase in DM content of silage for the two varieties of corn, but this was associated with significantly greater (P < 005) DM intake and fat-corrected milk production for only the earlier-maturing variety (Pride 5). Harvest date had no influence on solids-not-fat (SNF) content of the milk or body weight, but silage from Pride 5 corn resulted in a significantly (P < 0.05) higher SNF content and greater loss in body weight. In experiment II, feeding 4.7 kg of hay per day significantly reduced (P < 0.05) silage dry-matter intake and increased total ration dry-matter intake but did not change milk production or composition when compared with feeding 2.3 kg of hay per day. In experiment III, ear silage, stalk and leaf silage and hay were compared as a source of roughage for lactating cows. Total ration dry-matter intake was significantly greater (P < 0.05) for hay fed alone, but milk production was apparently higher when the ear silage was fed.