Submitted to: Journal Dairy Science Supplement
Publication Type: Abstract only
Publication Acceptance Date: 6/25/1997
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: A study was conducted to determine the influence of ruminally undegraded intake protein (UIP) on lactation performance of cows grazing permanent pasture. Thirty-six cows between 21 to 109 DIM and yielding 29.5 to 45.4 kg of milk/d were randomly assigned to three treatments. Cows in all treatments were grazed as a single group under an intensive rotational grazing system. The experiment lasted 11 weeks. The pasture contained primarily bluegrass, quackgrass, bromegrass and white clover. In addition to the pasture, cows were offered a concentrate mix containing 3.4% minerals and vitamins plus either 96.6% high moisture ear corn (HMEC) (Corn) or 78.4% HMEC and 18.2% roasted soybeans (RSB1), or 60.2% HMEC and 36.4% roasted soybeans (RSB2) on DM basis. Concentrate mixes (DM basis) had CP: 7.6%, 13.7% and 19.9%; UIP: 3.9%, 7.0% and 10.0% in the Corn, RSB1 and RSB2 treatments, respectively. During the grazing season pasture contained an average of 19.9% CP, 46.7% NDF, and 29.5% ADF (DM basis). In the presen study, feeding additional UIP and oil through roasted soybeans did not improve performance of grazing dairy cows.