| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Department of Animal Science, University of Nebraska, Lincoln 68583-0908
2 Department of Animal Science and School of Biological Sciences and Center for Biotechnology, University of Nebraska, Lincoln 68583-0908
Two experiments were conducted to determine effects of soybean hulls, soy lecithin, and soapstock mixtures on ruminal fermentation, milk composition, and ruminal microbial populations. In Experiment 1, 20 Holstein dairy cows were assigned to one of five total mixed rations (TMR) in replicated 5 x 5 Latin squares to measure the effect of TMR on intake and milk composition. Four ruminally fistulated cows were used in a 4 x 5 Youden square to measure the effect of TMR on ruminal fermentation. The TMR consisted of 40 or 50% alfalfa and corn silages, 13% soybean hulls, and 47 or 37% of a concentrate containing either 2.25% soybean oil; 2.25% lipid from a mixture of soybean hulls, soy lecithin, and soapstock; or no added lipid. The ratios of soy lecithin to soapstock evaluated were 1:1, 2.5:1, and 4:1 (dry basis). The TMR containing soy lecithin and soapstock at ratios of 1:1 and 2.5:1 resulted in higher milk C18:2 than did the soybean oil TMR. Rate of ruminal NDF digestion of soybean hulls was reduced for the soybean oil TMR.
In Experiment 2, a semi-continuous culture system was used to determine effects of soybean oil or an optimal mixture of soy lecithin and soapstock (1:1, wt/wt) on fermentation of soybean hulls and microbial populations. The TMR containing the lipid mixture increased the ratio of acetate to propionate compared with the TMR containing soybean oil and resulted in higher total protozoal counts than did the control TMR. The TMR containing mixtures of soy lecithin and soapstock at ratios of 1:1 and 2.5:1 elevated milk C18:2, and no negative effect on NDF digestion was detected, indicating some degree of ruminal protection.
Key Words: rumen • lecithin • soapstock • semi-continuous culture
Submitted on May 23, 1997
Accepted on September 15, 1997
This article has been cited by other articles:
|
|
 |
|
  J. L. Firkins, B. S. Oldick, J. Pantoja, C. Reveneau, L. E. Gilligan, and L. Carver Efficacy of Liquid Feeds Varying in Concentration and Composition of Fat, Nonprotein Nitrogen, and Nonfiber Carbohydrates for Lactating Dairy Cows J Dairy Sci, May 1, 2008; 91(5): 1969 - 1984. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. L. Boken, C. R. Staples, L. E. Sollenberger, T. C. Jenkins, and W. W. Thatcher Effect of Grazing and Fat Supplementation on Production and Reproduction of Holstein Cows J Dairy Sci, December 1, 2005; 88(12): 4258 - 4272. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. R. Ipharraguerre and J. H. Clark Soyhulls as an Alternative Feed for Lactating Dairy Cows: A Review J Dairy Sci, April 1, 2003; 86(4): 1052 - 1073. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
