| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Department of Animal Sciences, The Ohio State University, Columbus 43210
Corresponding author: M. L. Eastridge; e-mail: eastridge.1{at}osu.edu.
The pattern of biohydrogenation of fatty acids from fresh alfalfa or alfalfa hay supplemented with 3 concentrations (0, 4, and 8%) of sucrose was studied at a constant pH of 6.2. Four continuous culture fermenters were used in a 4 x 4 Latin square design to test the hypothesis that fresh forage would increase flow of vaccenic acid (VA) from the fermenters compared with the same forage in hay form and that this difference would be diminished by adding sucrose to the hay diet by changing the bacterial community profile. Effluent was collected from each of the 4 fermenters during the last 3 d of each 10-d period. Nutrient digestibility, volatile fatty acids (VFA), and fatty acids in the effluent were measured. Flow of bacterial organic matter (OM) and neutral and acid detergent fiber and acid detergent fiber digestibilities were higher for fresh alfalfa than alfalfa hay. True OM digestibility of alfalfa hay tended to linearly decrease with sucrose supplementation. However, microbial efficiency and flow of bacterial OM (g/d) linearly increased with sucrose addition. There was no change in total VFA concentration; however, proportion of acetate linearly decreased and proportion of butyrate linearly increased with sucrose addition. Fresh alfalfa increased total biohydrogenation of fatty acids compared with than hay. Vaccenic acid flow (mg/d) was much higher for fresh alfalfa compared with alfalfa hay (216 vs. 41) and VA was the predominant 18:1 isomer, followed by trans-13 18:1; however, sucrose had no effect on VA flow. The percentage of VA (of total trans-18:1) was not different between fresh alfalfa and hay, whereas percentage of trans-10 18:1 was much lower for fresh alfalfa. Therefore, the ratio of VA to trans-10 18:1 was higher for fresh alfalfa. Flow of trans-12 18:1 linearly increased, whereas flows of cis-12 and total cis-18:1 had quadratic responses to sucrose supplementation. Total biohydrogenation and biohydrogenation of linoleic and linolenic acids linearly decreased with sucrose; however, there was no effect of sucrose on total trans fatty acid flow. Sucrose may be more detrimental to the last step of biohydrogenation of VA. The effects of sucrose on biohydrogenation and concentration of VFA may have been caused by a shift in microbial population by mechanisms that are independent of pH.
Key Words: alfalfa • sucrose • fatty acids • biohydrogenation
Abbreviation key: 18C = 18-carbon, BH = biohydrogenation, CLA = conjugated linoleic acid, FA = fatty acids, RIS = ribosomal intergenic spacer, RIS-LP = ribosomal intergenic spacer length polymorphism, UFA = unsaturated fatty acids, VA = vaccenic acid.
This article has been cited by other articles:
|
|
 |
|
  S. K. R. Karnati, J. T. Sylvester, C. V. D. M. Ribeiro, L. E. Gilligan, and J. L. Firkins Investigating unsaturated fat, monensin, or bromoethanesulfonate in continuous cultures retaining ruminal protozoa. I. Fermentation, biohydrogenation, and microbial protein synthesis J Dairy Sci, August 1, 2009; 92(8): 3849 - 3860. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. K. R. Karnati, Z. Yu, and J. L. Firkins Investigating unsaturated fat, monensin, or bromoethanesulfonate in continuous cultures retaining ruminal protozoa. II. Interaction of treatment and presence of protozoa on prokaryotic communities J Dairy Sci, August 1, 2009; 92(8): 3861 - 3873. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. B. Penner and M. Oba Increasing dietary sugar concentration may improve dry matter intake, ruminal fermentation, and productivity of dairy cows in the postpartum phase of the transition period J Dairy Sci, July 1, 2009; 92(7): 3341 - 3353. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. B. Penner, L. L. Guan, and M. Oba Effects of feeding Fermenten on ruminal fermentation in lactating Holstein cows fed two dietary sugar concentrations J Dairy Sci, April 1, 2009; 92(4): 1725 - 1733. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
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]
|
|
|
|
|
|
A. A. AbuGhazaleh, D. O. Felton, and S. A. Ibrahim Milk Conjugated Linoleic Acid Response to Fish Oil and Sunflower Oil Supplementation to Dairy Cows Managed Under Two Feeding Systems J Dairy Sci, October 1, 2007; 90(10): 4763 - 4769. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. V. D. M. Ribeiro, M. L. Eastridge, J. L. Firkins, N. R. St-Pierre, and D. L. Palmquist Kinetics of Fatty Acid Biohydrogenation In Vitro J Dairy Sci, March 1, 2007; 90(3): 1405 - 1416. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
