|
|
||||||||
Dairy Science Department, South Dakota State University, Brookings 57007
ABSTRACT
An experiment with 12 cows in switchback design determined the feeding value of a heat-treated soybean product. Treatments were regular soybean meal with 44% crude protein, commercially available heat-treated soybeans, and unheated soybeans. Concentrate mixes of protein sources and corn were formulated to contain 15% crude protein and fed at 1 kg/3 kg milk. Forage portion of the diet consisted of 2.3 kg alfalfa hay per day and corn silage ad libitum. Nitrogen solubilities of the protein supplement sources in 10% Burroughs' buffer solution were 13.8, 9.4, and 25.4%, and averaged 29.4, 28.9, and 33.2% for the total rations. Cows averaged 7 wk postpartum at the start of the experiment, which consisted of three 4-wk periods. Production of milk was similar for all treatments. Means for cows fed soybean meal, heat-treated soybeans, and unheated soybeans were 28.6, 29.1, and 28.3 kg/day. No differences were in milk fat (3.57, 3.61, and 3.53%) or total solids (12.16, 12.12, and 12.13%). Protein percent in milk was lower for heat-treated and unheated soybeans (3.00, 2.92, and 2.93%), probably because of the higher fat content of those diets. Amounts of long chain unsaturated fatty acids in milk fat were higher for soybean diets. Heating soybeans improved their value slightly as a feed for lactating cows, but milk production by cows past peak production was not significantly greater than production with conventional corn-soybean meal diets.
1 Published with the approval of the Director of the South Dakota Agricultural Experiment Station as Publication No. 1715 of the journal series.
This article has been cited by other articles:
![]() |
C. Paradis, R. Berthiaume, C. Lafreniere, R. Gervais, and P. Y. Chouinard Conjugated linoleic acid content in adipose tissue of calves suckling beef cows on pasture and supplemented with raw or extruded soybeans J Anim Sci, July 1, 2008; 86(7): 1624 - 1636. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. R. Ipharraguerre and J. H. Clark Impacts of the Source and Amount of Crude Protein on the Intestinal Supply of Nitrogen Fractions and Performance of Dairy Cows J Dairy Sci, May 1, 2005; 88(e_suppl_1): E22 - E37. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Orias, C. G. Aldrich, J. C. Elizalde, L. L Bauer, and N. R. Merchen The effects of dry extrusion temperature of whole soybeans on digestion of protein and amino acids by steers J Anim Sci, September 1, 2002; 80(9): 2493 - 2501. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |