Milk Production of Fall-Calving Dairy Cows During Summer Grazing of Grass or Grass-Clover Pasture

¹ Department of Dairy Science, University of Wisconsin, Madison 53706
² US Dairy Forage Research Center, USDA-ARS
³ Department of Dairy Science, University of Wisconsin, Madison 53706 and US Dairy Forage Research Center, USDA-ARS

Milk production of fall-calving dairy cows during subsequent summer grazing was evaluated in two consecutive years using a total of 80 mid- to late-lactation Holsteins. Cows calved during September and October and grazed from April to August in the following year. In yr 1, 27 cows grazed a native grass pasture and 13 cows grazed a native grass-clover mixed pasture containing 26% red clover and white clover. In yr 2, 40 cows grazed native grass pasture as one group. Also, cows in yr 2 were administered bovine somatotropin, whereas in yr 1, no bST was used. Grazing cows also were fed concentrate supplements at 6.2 kg/d of dry matter (DM) in yr 1 and 7.9 kg/d of DM in yr 2 to provide 35 to 40% of total intake. Average daily milk during the grazing period decreased 3.6 kg in yr 1 and 7.7 kg in yr 2 when compared with milk yield extrapolated from the lactation curve established 10 wk before being turned out to pasture. Estimated DM intake during grazing was also less than what would have been expected had cows continued on a total mixed ration in confinement. Cows grazing the mixed pasture of grass and clover yielded 1.3 kg/d more milk than those grazing the grass pasture in yr 1. A decrease in milk resulting from the change from total mixed ration fed in confinement to grazing supplemented with concentrates was not avoided with these mid- to late-lactation cows, but the cumulative loss over the lactation was less than with early lactation cows in a companion study. Clover enhances the grazing value of pasture when grown with grasses.

Key Words: pasture • grass • clover • milk production

Submitted on August 8, 2000
Accepted on December 5, 2000

This article has been cited by other articles:

				F. Bargo, L. D. Muller, J. E. Delahoy, and T. W. Cassidy Performance of High Producing Dairy Cows with Three Different Feeding Systems Combining Pasture and Total Mixed Rations J Dairy Sci, November 1, 2002; 85(11): 2948 - 2963. [Abstract] [Full Text] [PDF]